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KOMATSU PC78UU-6 PC78US-6 SHOP MANUAL SEBM025119 – PDF DOWNLOAD
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Description
KOMATSU PC78UU-6 PC78US-6 SHOP MANUAL SEBM025119 – PDF DOWNLOAD
FILE DETAILS:
KOMATSU PC78UU-6 PC78US-6 SHOP MANUAL SEBM025119 – PDF DOWNLOAD
Language : English
Pages : 1090
Downloadable : Yes
File Type : PDF
IMAGES PREVIEW OF THE MANUAL:
DESCRIPTION:
KOMATSU PC78UU-6 PC78US-6 SHOP MANUAL SEBM025119 – PDF DOWNLOAD
GENERAL
This shop manual has been prepared as an aid to improve the quality of repairs by giving the serviceman an
accurate understanding of the product and by showing him the correct way to perform repairs and make judgements.
Make sure you understand the contents of this manual and use it to full effect at every opportunity.
This shop manual mainly contains the necessary technical information for operations performed in a service
workshop. For ease of understanding, the manual is divided into the following chapters; these chapters are further
divided into the each main group of components.
STRUCTURE AND FUNCTION
This section explains the structure and function of each component. It serves not only to give an understanding
of the structure, but also serves as reference material for troubleshooting.
In addition, this section may contain hydraulic circuit diagrams, electric circuit diagrams, and maintenance
standards.
TESTING AND ADJUSTING
This section explains checks to be made before and after performing repairs, as well as adjustments to
be made at completion of the checks and repairs.
Troubleshooting charts correlating “Problems” with “Causes” are also included in this section.
DISASSEMBLY AND ASSEMBLY
This section explains the procedures for removing, installing, disassembling and assembling each component,
as well as precautions for them.
MAINTENANCE STANDARD
This section gives the judgment standards for inspection of disassembled parts.
The contents of this section may be described in STRUCTURE AND FUNCTION.
OTHERS
This section mainly gives hydraulic circuit diagrams and electric circuit diagrams.
In addition, this section may give the specifications of attachments and options together.
TABLE OF CONTENTS:
KOMATSU PC78UU-6 PC78US-6 SHOP MANUAL SEBM025119 – PDF DOWNLOAD
COVER............................................................................................................................................................................................................................. 1 CONTENTS.......................................................................................................................................................................................................................... 2 LIST OF REVISED PAGES............................................................................................................................................................................................................. 3 SAFETY............................................................................................................................................................................................................................ 9 SAFETY NOTICE................................................................................................................................................................................................................. 9 FOREWORD.......................................................................................................................................................................................................................... 11 GENERAL....................................................................................................................................................................................................................... 11 HOW TO READ THE SHOP MANUAL................................................................................................................................................................................................... 12 HOISTING INSTRUCTIONS......................................................................................................................................................................................................... 13 METHOD OF DISASSEMBLING, CONNECTING PUSH-PULL TYPE COUPLER.................................................................................................................................................................... 14 COATING MATERIALS............................................................................................................................................................................................................. 16 STANDARD TIGHTENING TORQUE.................................................................................................................................................................................................... 18 ELECTRIC WIRE CODE............................................................................................................................................................................................................ 21 CONVERSION TABLE.............................................................................................................................................................................................................. 22 UNITS......................................................................................................................................................................................................................... 28 01 GENERAL........................................................................................................................................................................................................................ 29 SPECIFICATION DIMENSIONS DRAWING.............................................................................................................................................................................................. 30 WORKING RANGE DRAWING......................................................................................................................................................................................................... 32 SPECIFICATIONS................................................................................................................................................................................................................ 34 WEIGHT TABLE.................................................................................................................................................................................................................. 46 LIST OF LUBRICANTS AND COOLANT................................................................................................................................................................................................ 50 10 STRUCTURE, FUNCTION AND MAINTENANCE STANDARD................................................................................................................................................................................... 51 PTO........................................................................................................................................................................................................................... 52 COOLING SYSTEM................................................................................................................................................................................................................ 54 POWER TRAIN SYSTEM............................................................................................................................................................................................................ 56 SWING CIRCLE.................................................................................................................................................................................................................. 58 SWING MACHINERY............................................................................................................................................................................................................... 60 TRACK FRAME AND IDLER CUSHION................................................................................................................................................................................................. 64 IDLER......................................................................................................................................................................................................................... 66 TRACK ROLLER.................................................................................................................................................................................................................. 67 CARRIER ROLLER................................................................................................................................................................................................................ 69 SPROCKET...................................................................................................................................................................................................................... 70 TRACK SHOE.................................................................................................................................................................................................................... 71 ARRANGEMENT OF HYDRAULIC COMPONENTS........................................................................................................................................................................................... 76 HYDRAULIC TANK AND OIL FILTER................................................................................................................................................................................................. 79 CENTER SWIVEL JOINT........................................................................................................................................................................................................... 81 TRAVEL MOTOR.................................................................................................................................................................................................................. 83 WORK EQUIPMENT CYLINDER....................................................................................................................................................................................................... 91 SOLENOID VALVE................................................................................................................................................................................................................ 96 MULTI-CONTROL VALVE........................................................................................................................................................................................................... 103 ACCUMULATOR FOR BRAKER........................................................................................................................................................................................................ 104 HYDRAULIC PUMP................................................................................................................................................................................................................ 105 CONTROL VALVE................................................................................................................................................................................................................. 130 CLSS.......................................................................................................................................................................................................................... 170 SWING MOTOR................................................................................................................................................................................................................... 208 WORK EQUIPMENT AND SWING PPC VALVE............................................................................................................................................................................................ 216 TRAVEL PPC VALVE.............................................................................................................................................................................................................. 222 OFFSET PPC VALVE (PC78UU-6) ATTACHMENT PPC VALVE (PC78US-6) BLADE PPC VALVE (PC78UU, PC78US-6).............................................................................................................................. 226 WORK EQUIPMENT................................................................................................................................................................................................................ 230 DIMENSIONS OF EACH PART OF WORK EQUIPMENT..................................................................................................................................................................................... 236 AIR CONDITIONER PIPING (OPTIONAL)............................................................................................................................................................................................. 242 ELECTRIC CONTROL SYSTEM....................................................................................................................................................................................................... 245 SYSTEM COMPONENTS............................................................................................................................................................................................................. 302 MONITOR SYSTEM................................................................................................................................................................................................................ 315 SENSORS....................................................................................................................................................................................................................... 321 20 TESTING AND ADJUSTING.......................................................................................................................................................................................................... 325 STANDARD VALUE TABLE.......................................................................................................................................................................................................... 326 STANDARD VALUE TABLE FOR ENGINE........................................................................................................................................................................................... 326 STANDARD VALUE TABLE FOR CHASSIS.......................................................................................................................................................................................... 329 STANDARD VALUE TABLE FOR ELECTRIC PARTS................................................................................................................................................................................... 338 TESTING AND ADJUSTING......................................................................................................................................................................................................... 349 LIST OF DEVICES FOR TESTING, ADJUSTING, & TROUBLESHOOTING................................................................................................................................................................. 350 MEASURING ENGINE SPEED.................................................................................................................................................................................................... 351 MEASURING EXHAUST GAS COLOR............................................................................................................................................................................................... 352 ADJUSTING VALVE CLEARANCE................................................................................................................................................................................................. 353 MEASURING COMPRESSION PRESSURE............................................................................................................................................................................................ 354 MEASURING BLOW-BY PRESSURE................................................................................................................................................................................................ 356 TESTING AND ADJUSTING FUEL INJECTION TIMING............................................................................................................................................................................... 358 MEASURING ENGINE OIL PRESSURE............................................................................................................................................................................................. 362 ADJUSTING ENGINE STOP SOLENOID............................................................................................................................................................................................ 364 ADJUSTING FUEL CONTROL LINKAGE............................................................................................................................................................................................ 366 ADJUSTING ENGINE SPEED SENSOR............................................................................................................................................................................................. 368 TESTING AND ADJUSTING HYDRAULIC PRESSURE IN WORK EQUIPMENT, SWING, AND TRAVEL CIRCUITS.................................................................................................................................... 370 MEASURING LS DIFFERENTIAL PRESSURE AND ADJUSTING LS VALVE................................................................................................................................................................. 373 ADJUSTING PC VALVE........................................................................................................................................................................................................ 375 TESTING TVC-EPC SOLENOID OUTPUT PRESSURE.................................................................................................................................................................................. 375 MEASURING CONTROL CIRCUIT PRESSURE........................................................................................................................................................................................ 378 MEASURING PPC VALVE OUTPUT PRESSURE....................................................................................................................................................................................... 379 TESTING SOLENOID VALVE OUTPUT PRESSURE.................................................................................................................................................................................... 380 ADJUSTING WORK EQUIPMENT VALVE AND SWING PPC VALVE........................................................................................................................................................................ 382 TESTING TRAVEL DEVIATION.................................................................................................................................................................................................. 383 TESTING PARTS WHICH CAN CAUSE HYDRAULIC DRIFT OF WORK EQUIPMENT........................................................................................................................................................... 385 MEASURING OIL LEAKAGE FROM SWING AND TRAVEL MOTORS........................................................................................................................................................................ 386 RELEASING RESIDUAL PRESSURE FROM HYDRAULIC CIRCUIT........................................................................................................................................................................ 387 TESTING CLEARANCE OF SWING CIRCLE BEARING................................................................................................................................................................................. 388 TESTING AND ADJUSTING TRACK SHOE TENSION.................................................................................................................................................................................. 389 BLEEDING AIR FROM HYDRAULIC CIRCUIT....................................................................................................................................................................................... 390 PROCEDURE FOR ADJUSTING INSTALLATION OF LONG ARM.......................................................................................................................................................................... 392 TESTING AND ADJUSTING HOOD CATCH.......................................................................................................................................................................................... 393 REPLACEMENT PROCEDURE OF POTENTIOMETERS................................................................................................................................................................................... 395 PROCEDURE FOR TESTING DIODE............................................................................................................................................................................................... 396 Pm-CLINIC SERVICE......................................................................................................................................................................................................... 397 TROUBLESHOOTING............................................................................................................................................................................................................... 401 POINTS TO REMEMBER WHEN TROUBLESHOOTING................................................................................................................................................................................... 402 SEQUENCE OF EVENTS IN TROUBLESHOOTING..................................................................................................................................................................................... 403 PRECAUTIONS WHEN CARRYING OUT MAINTENANCE................................................................................................................................................................................. 404 CHECKS BEFORE TROUBLESHOOTING............................................................................................................................................................................................. 412 CONNECTOR TYPES AND MOUNTING LOCATIONS (PC78US-6 Serial No.: 4001 – 5500)................................................................................................................................................. 414 CONNECTOR ARRANGEMENT DIAGRAM (PC78US-6 Serial No.: 4001 – 5500).......................................................................................................................................................... 416 CONNECTOR TYPES AND MOUNTING LOCATIONS (PC78US-6 Serial No.: 5501 – 6500)................................................................................................................................................. 419 CONNECTOR ARRANGEMENT DIAGRAM (PC78US-6 Serial No.: 5501 – 6500).......................................................................................................................................................... 422 CONNECTOR TYPES AND MOUNTING LOCATIONS (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................. 425 CONNECTOR ARRANGEMENT DIAGRAM (PC78US-6 Serial No.: 6501 and up)......................................................................................................................................................... 428 CONNECTOR TYPES AND MOUNTING LOCATIONS (PC78UU-6 Serial No.: 22832 – 23500)............................................................................................................................................... 431 CONNECTOR ARRANGEMENT DIAGRAM (PC78UU-6 Serial No.: 22832 – 23500)........................................................................................................................................................ 434 CONNECTOR TYPES AND MOUNTING LOCATIONS (PC78UU-6 Serial No.: 23501 and up)................................................................................................................................................ 437 CONNECTOR ARRANGEMENT DIAGRAM (PC78UU-6 Serial No.: 23501 and up)......................................................................................................................................................... 440 CONNECTION TABLE FOR CONNECTOR PIN NUMBERS................................................................................................................................................................................ 444 EXPLANATION OF FUNCTIONS OF ELECTRIC SYSTEM CONTROL MECHANISM............................................................................................................................................................. 468 DISPLAY AND SPECIAL FUNCTIONS OF MONITOR PANEL............................................................................................................................................................................ 472 TVC VALVE CURRENT ADJUSTMENT TABLE........................................................................................................................................................................................ 491 HOW TO READ JUDGMENT TABLE................................................................................................................................................................................................ 493 CONTENTS AND PROCEDURE OF TROUBLESHOOTING................................................................................................................................................................................. 498 TROUBLESHOOTING OF COMMUNICATION SYSTEM (N MODE).......................................................................................................................................................................... 499 N-1 Defective communication........................................................................................................................................................................................... 500 TROUBLESHOOTING FOR CONTROLLER (GOVERNOR CONTROL SYSTEM) (E MODE)......................................................................................................................................................... 503 PRECAUTIONS FOR TROUBLESHOOTING FOR CONTROLLER (GOVERNOR CONTROL SYSTEM).............................................................................................................................................. 504 ACTION TAKEN BY CONTROLLER WHEN TROUBLE OCCURS AND PROBLEMS ON MACHINE................................................................................................................................................ 506 JUDGMENT TABLE FOR CONTROLLER (GOVERNOR CONTROL SYSTEM) AND ENGINE.................................................................................................................................................... 512 E-1 Controller power supply is defective (LED of controller is turned off)............................................................................................................................................ 516 E-2 [E321] (Short circuit in motor drive relay) is displayed.......................................................................................................................................................... 519 E-3 [E323] (Short circuit in accelerator relay system) is displayed................................................................................................................................................... 520 E-4 [E325] (Short circuit in decelerator relay system) is displayed................................................................................................................................................... 523 E-5 [E328] (Stall of motor) is displayed.............................................................................................................................................................................. 528 E-6 [E227] (Trouble in engine speed sensor) is displayed.............................................................................................................................................................. 534 E-7 [E306] Trouble in governor motor feedback potentiometer is displayed.............................................................................................................................................. 536 E-8 [E308] Trouble in fuel control dial system is displayed........................................................................................................................................................... 537 E-9 One-touch slow-down mechanism does not work....................................................................................................................................................................... 539 E-10 Engine does not start............................................................................................................................................................................................ 542 a) [E304] Short circuit in engine stop solenoid relay system is displayed......................................................................................................................................... 542 b) [E314] Disconnection in engine stop solenoid relay system is displayed......................................................................................................................................... 542 c) Engine stop solenoid system.................................................................................................................................................................................... 545 d) Starting System................................................................................................................................................................................................ 550 E-11 Engine does not stop............................................................................................................................................................................................. 557 TROUBLESHOOTING FOR CONTROLLER PUMP CONTROL SYSTEM (C MODE)............................................................................................................................................................... 561 PRECAUTIONS FOR TROUBLESHOOTING FOR CONTROLLER (PUMP CONTROL SYSTEM).................................................................................................................................................. 562 ACTION TAKEN BY CONTROLLER WHEN TROUBLE OCCURS AND PROBLEMS ON MACHINE................................................................................................................................................ 564 JUDGEMENT TABLE FOR CONTROLLER (PUMP CONTROL SYSTEM) AND HYDRAULIC EQUIPMENT.......................................................................................................................................... 570 ELECTRIC CIRCUIT DIAGRAM OF C MODE SYSTEM............................................................................................................................................................................. 574 C-1 [E232] Trouble in TVC-EPC solenoid system......................................................................................................................................................................... 585 C-2 [E233] Trouble in TVC-EPC solenoid system......................................................................................................................................................................... 585 C-3 [E203] Trouble in swing holding brake solenoid system............................................................................................................................................................. 588 C-4 [E213] Trouble in swing holding brake solenoid system............................................................................................................................................................. 588 C-5 [E206] Trouble in 2nd travel speed selection solenoid system...................................................................................................................................................... 591 C-6 [E216] Trouble in 2nd travel speed selection solenoid system...................................................................................................................................................... 591 C-7 [E403] Trouble in boom angle sensor correction (Only PC78UU-6).................................................................................................................................................... 594 C-8 [E406] Trouble in arm angle sensor correction (Only PC78UU-6)..................................................................................................................................................... 594 C-9 [E411] Trouble in offset boom angle sensor correction (Only PC78UU-6)............................................................................................................................................. 594 C-10 [E441] Trouble in interference prevention (front) correction (Only PC78UU-6)..................................................................................................................................... 596 C-11 [E442] Trouble in interference prevention (side) correction (Only PC78UU-6)...................................................................................................................................... 596 C-12 [E443] Trouble in depth indication correction (Only PC78UU-6).................................................................................................................................................... 597 C-13 [E258] Short circuit in 5V system of sensor power supply (Only PC78UU-6)......................................................................................................................................... 598 C-14 [E224] Trouble in pump pressure sensor is displayed.............................................................................................................................................................. 601 C-15 [E401] Trouble in boom angle sensor system(Only PC78UU-6)........................................................................................................................................................ 603 C-16 [E402] Trouble in boom angle sensor system (Only PC78UU-6)....................................................................................................................................................... 603 C-17 [E404] Trouble in arm angle sensor system(Only PC78UU-6)......................................................................................................................................................... 604 C-18 [E405] Trouble in arm angle sensor system (Only PC78UU-6)........................................................................................................................................................ 604 C-19 [E407] Trouble in offset angle sensor system (Only PC78UU-6)..................................................................................................................................................... 605 C-20 [E408] Trouble in offset angle sensor system (Only PC78UU-6)..................................................................................................................................................... 605 C-21 [E421] Short circuit in boom raise EPC system is displayed (Only PC78UU-6)....................................................................................................................................... 606 C-22 [E422] Disconnection in boom raise EPC system is displayed (Only PC78UU-6)....................................................................................................................................... 607 C-23 [E423] Short circuit or grounding fault in arm-in EPC system is displayed (Only PC78UU-6)........................................................................................................................ 608 C-24 [E424] Disconnection in arm-in EPC system is displayed (Only PC78UU-6)........................................................................................................................................... 609 C-25 [E425] Short circuit or grounding fault in offset left EPC system is displayed (Only PC78UU-6)................................................................................................................... 610 C-26 [E426] Disconnection in offset left EPC system is displayed (Only PC78UU-6)...................................................................................................................................... 611 C-27 [E431] Short circuit or grounding fault in PPC basic pressure lock solenoid system is displayed (Only PC78UU-6).................................................................................................. 612 C-28 Boom does not stop automatically at normal position but interferes when it is raised (Only PC78UU-6)............................................................................................................. 615 C-29 Arm does not stop automatically at normal position but interferes when it is moved in (Only PC78UU-6)............................................................................................................ 616 C-30 Offset does not stop automatically at normal position but interferes when it is moved to left (Only PC78UU-6).................................................................................................... 617 C-31 Work equipment stops far or near (Only PC78UU-6)................................................................................................................................................................. 618 C-32 Buzzer sounds for 7 seconds while emergency work equipment operation switch is not turned ON (Only PC78UU-6)..................................................................................................... 619 C-33 Boom raise end cushion does not work at all or normally (Only PC78UU-6).......................................................................................................................................... 622 C-34 Arm-in end cushion does not work at all or normally (Only PC78UU-6).............................................................................................................................................. 623 C-35 Offset end cushion does not work at all or normally (Only PC78UU-6).............................................................................................................................................. 624 C-36 Work equipment stops after or before set height (Only PC78UU-6).................................................................................................................................................. 625 C-37 When depth display is reset, 0.0 m is not indicated at GL (Only PC78UU-6)........................................................................................................................................ 626 C-38 Work equipment still moves after work equipment lock lever is set to LOCK........................................................................................................................................ 627 C-39 Machine does not swing........................................................................................................................................................................................... 632 C-40 Travel speed does not rise....................................................................................................................................................................................... 635 C-41 Gear speed does not change automatically......................................................................................................................................................................... 636 C-42 Trouble in controller power supply system (LED of controller is turned OFF)...................................................................................................................................... 636 TROUBLESHOOTING FOR CONTROLLER (INPUT SIGNAL SYSTEM) (F MODE)............................................................................................................................................................. 637 F-1 Bit pattern 1023-(4) Swing pressure switch does not light up...................................................................................................................................................... 638 F-2 Bit pattern 1023-(3) Travel pressure switch does not light up..................................................................................................................................................... 640 F-3 Bit pattern 1023-(6) Boom RAISE pressure switch does not light up................................................................................................................................................. 642 F-4 Bit pattern 1023-(5) Arm IN pressure switch does not light up..................................................................................................................................................... 644 F-5 Bit pattern 1026-(1) Deceleration switch of left knob does not light up........................................................................................................................................... 646 F-6 Bit pattern 1026-(4) 2nd travel speed selection switch (pedal) does not light up (US with blade specification and UU)............................................................................................. 648 F-7 Bit pattern 1021-(3) Compressor signal does not light up.......................................................................................................................................................... 649 F-8 Bit pattern 1026-(3) Emergency work equipment operation switch does not light up (Only PC78UU-6).................................................................................................................. 651 TROUBLESHOOTING FOR HYDRAULIC AND MECHANICAL SYSTEMS (H MODE)............................................................................................................................................................. 653 TABLE OF HYDRAULIC FAILURE MODES AND THEIR CAUSES..................................................................................................................................................................... 656 H-1 Speed or power of 2 or more systems of work equipment (boom, arm, bucket), travel, swing, and blade is low........................................................................................................ 658 a) Speed or power of work equipment (including blade), travel, and swing systems is low........................................................................................................................... 658 b) Speed or power of all work equipment (excluding blade) and travel is low....................................................................................................................................... 659 c) Speed or power of swing and blade is low....................................................................................................................................................................... 659 d) Speed or power of travel and blade is low...................................................................................................................................................................... 660 e) Speed or power of all work equipment (excluding blade) is low.................................................................................................................................................. 660 f) Speed or power of travel and swing is low...................................................................................................................................................................... 661 g) Speed or power of all work equipment and swing is low.......................................................................................................................................................... 661 H-2 Engine speed lowers extremely or engine stalls.................................................................................................................................................................... 662 H-3 2 or more systems of work equipment (boom, arm, bucket), travel, swing, and blade do not move..................................................................................................................... 664 a) All work equipment (including blade), travel, and swing systems do not move.................................................................................................................................... 664 b) All work equipment (excluding blade) and travel systems do not move............................................................................................................................................ 665 c) Swing and blade systems do not move............................................................................................................................................................................ 665 d) Travel and blade systems do not move........................................................................................................................................................................... 666 e) All work equipment (excluding blade) does not move............................................................................................................................................................. 666 H-4 Abnormal sound comes out (from around pump)....................................................................................................................................................................... 667 H-5 Fine controllability or response is low........................................................................................................................................................................... 668 H-6 Hydraulic drift is large (all work equipment and blade)........................................................................................................................................................... 669 H-7 Boom speed or power is low (other work equipment is normal)....................................................................................................................................................... 670 a) Boom RAISE speed or power is low............................................................................................................................................................................... 670 b) Boom LOWER speed or power is low............................................................................................................................................................................... 671 H-8 Arm speed or power is low (Other work equipment is normal)........................................................................................................................................................ 672 a) Arm IN speed or power is low................................................................................................................................................................................... 672 b) Arm OUT speed or power is low.................................................................................................................................................................................. 675 H-9 Bucket speed or power is low (Other work equipment is normal)..................................................................................................................................................... 676 a) Bucket CURL speed or power is low.............................................................................................................................................................................. 676 b) Bucket DUMP speed or power is low.............................................................................................................................................................................. 677 H-10 Offset speed or power is low (other work equipment is normal) (Only PC78UU-6).................................................................................................................................... 678 a) Offset left speed or power is low.............................................................................................................................................................................. 678 b) Offset right speed or power is low............................................................................................................................................................................. 679 H-11 Boom does not move............................................................................................................................................................................................... 680 a) Boom does not rise............................................................................................................................................................................................. 680 b) Boom does not lower............................................................................................................................................................................................ 681 H-12 Arm does not move................................................................................................................................................................................................ 682 a) Arm does not move in........................................................................................................................................................................................... 682 b) Arm does not move out.......................................................................................................................................................................................... 683 H-13 Bucket does not move............................................................................................................................................................................................. 684 a) Bucket does not curl........................................................................................................................................................................................... 684 b) Bucket does not dump........................................................................................................................................................................................... 685 H-14 Offset boom does not move (Only PC78UU-6)........................................................................................................................................................................ 686 a) Offset boom left does not move................................................................................................................................................................................. 686 b) Offset boom right does not move................................................................................................................................................................................ 687 H-15 H-16 Hydraulic drift of boom is large............................................................................................................................................................................ 688 H-16 Hydraulic drift of arm is large.................................................................................................................................................................................. 688 H-17 Hydraulic drift of bucket is large............................................................................................................................................................................... 689 H-18 Hydraulic drift of offset is large (Only PC78UU-6)............................................................................................................................................................... 689 a) Hydraulic drift of offset to left is large..................................................................................................................................................................... 689 b) Hydraulic drift of offset to right is large.................................................................................................................................................................... 689 H-19 Time lag is large (When engine speed is low)..................................................................................................................................................................... 690 H-20 Part loaded more moves slower in compound operation of work equipment............................................................................................................................................ 690 H-21 Boom RAISE speed is low in compound operation of swing and boom RAISE............................................................................................................................................ 691 H-22 Travel speed lowers extremely in compound operation of travel and boom RAISE..................................................................................................................................... 691 H-23 Speed is low in compound operation of work equipment relief and swing, work equipment relief and other work equipment............................................................................................ 691 H-24 Work equipment does not move or its speed is low in compound operation of travel and work equipment.............................................................................................................. 692 H-25 Travel deviation is large........................................................................................................................................................................................ 693 a) Travel deviation is large during ordinary travel............................................................................................................................................................... 693 b) Travel deviation is large when machine starts (but normal during ordinary travel).............................................................................................................................. 694 H-26 Travel deviation is large in compound operation of travel and swing, travel and work equipment................................................................................................................... 695 H-27 Travel speed or power is low (Work equipment, swing, and blade operations are normal)............................................................................................................................ 696 H-28 Machine cannot be steered sharply or steering force is insufficient.............................................................................................................................................. 698 H-29 Travel speed does not change at all or does not change quickly................................................................................................................................................... 699 H-30 Machine does not travel.......................................................................................................................................................................................... 700 H-30 Supplement....................................................................................................................................................................................................... 701 H-31 Overrun of travel is large....................................................................................................................................................................................... 702 H-32 Travel hydraulic drift is large.................................................................................................................................................................................. 702 H-33 Fine controllability or response is low.......................................................................................................................................................................... 703 H-34 Swing speed or power is low (Work equipment, travel, and blade operations are normal)............................................................................................................................ 704 H-35 Machine does not swing (Work equipment, travel, and blade operations are normal)................................................................................................................................. 707 a) Swing speed or power is low in both directions................................................................................................................................................................. 707 b) Swing speed or power is low in either direction................................................................................................................................................................ 708 H-36 Swing acceleration is low........................................................................................................................................................................................ 709 a) Swing acceleration is low in both directions................................................................................................................................................................... 709 b) Swing acceleration is low in either direction.................................................................................................................................................................. 709 H-37 Overrun of swing is large........................................................................................................................................................................................ 710 a) Overrun of swing is large in both directions................................................................................................................................................................... 710 b) Overrun of swing is large in either direction.................................................................................................................................................................. 710 H-38 Large shock is made when machine stops swinging.................................................................................................................................................................. 711 H-39 Large abnormal sound is made when machine stops swinging......................................................................................................................................................... 711 H-40 Swing hydraulic drift is large................................................................................................................................................................................... 712 H-41 Fine controllability or response of swing is low................................................................................................................................................................. 713 H-42 Blade speed or power is low (Work equipment, travel, and swing operations are normal)............................................................................................................................ 714 H-43 Blade does not move (Work equipment, travel, and swing operations are normal).................................................................................................................................... 715 a) Blade does not rise............................................................................................................................................................................................ 715 b) Blade does not lower........................................................................................................................................................................................... 716 H-44 Hydraulic drift of blade is large................................................................................................................................................................................ 717 H-45 Fine controllability or response of blade is low................................................................................................................................................................. 718 H-46 Monitor panel displays error code and boom RAISE, arm IN, and offset LEFT operations stop just before interference (Only PC78UU-6)............................................................................... 719 H-47 Machine does not stop boom RAISE, arm IN, and offset LEFT operations automatically but interferes (Only PC78UU-6)................................................................................................ 719 TROUBLESHOOTING FOR MACHINE MONITOR SYSTEM (M MODE)....................................................................................................................................................................... 721 ACTION TAKEN BY CONTROLLER WHEN TROUBLE OCCURS AND PROBLEMS ON MACHINE................................................................................................................................................ 722 ELECTRIC CIRCUIT DIAGRAM OF M MODE SYSTEM............................................................................................................................................................................. 724 M-1 [E101] (Error history data are abnormal) is displayed............................................................................................................................................................. 730 M-2 [E108] (Engine coolant temperature is 105 °C) is displayed........................................................................................................................................................ 732 M-3 [E112] (Wiper forward output is shorted) is displayed............................................................................................................................................................. 732 M-4 [E113] (Wiper reverse output is shorted) is displayed............................................................................................................................................................. 732 M-5 [E114] (Contact with washer output of 24 V) is displayed.......................................................................................................................................................... 732 M-6 [E115] (Wiper does not start wiping in 10 seconds) is displayed................................................................................................................................................... 732 M-7 [E116] (Wiper is not retracted in 10 seconds) is displayed........................................................................................................................................................ 732 M-8 When starting switch is turned to ON position, monitor panel segments do not light up for 3 seconds............................................................................................................... 733 a) Monitor panel segments do not light up at all (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)............................................................................................. 733 b) Some monitor panel segments do not light up (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)............................................................................................... 733 a) Monitor panel segments do not light up at all (PC78US-6 Serial No.: 6501 and up)............................................................................................................................... 734 b) Some monitor panel segments do not light up (PC78US-6 Serial No.: 6501 and up)................................................................................................................................. 734 M-9 When starting switch is set to ON position, all monitor panel segments light up but do not go off................................................................................................................. 735 M-10 While preheating is not executed, "Preheater monitor" lights up.................................................................................................................................................. 735 M-11 When starting switch is set to ON position and engine is started, basic check items flash........................................................................................................................ 736 a) Alternator system (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)......................................................................................................................... 736 a) Alternator system (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................... 737 b) Engine oil system (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)......................................................................................................................... 738 b) Engine oil system (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................... 739 M-12 When starting switch is set to ON position (but engine is stopped), caution items and emergency stop items (excluding battery and engine oil) flash.............................................................. 740 a) Alternator system (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)......................................................................................................................... 740 a) Alternator system (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................... 741 b) Engine oil pressure sensor system (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)......................................................................................................... 742 b) Engine oil pressure sensor system (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................... 743 M-13 When starting switch is set to ON position and engine is started, caution items and emergency stop items flash (When there is not abnormality in inspection items and engine before troubleshooting, however).... 744 a) "Engine oil" flashes........................................................................................................................................................................................... 744 b) "Charge level" flashes......................................................................................................................................................................................... 744 c) "Coolant temperature" flashes (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)............................................................................................................. 745 c) "Coolant temperature" flashes (PC78US-6 Serial No.: 6501 and up)............................................................................................................................................... 746 d) "Fuel level" flashes (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)...................................................................................................................... 747 d) "Fuel level" flashes (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................ 748 M-14 When starting switch is set to ON position (but engine is stopped), buzzer does not sound for 1 second While caution item is flashing, buzzer does not sound.................................................... 749 M-15 Monitor plane lamp for nighttime is not turned on (LC display is normal)......................................................................................................................................... 751 M-16 Coolant temperature gauge does not rise.......................................................................................................................................................................... 753 M-17 Coolant temperature gauge is not displayed (Gauge does not rise to 1st line during operation).................................................................................................................... 755 M-18 Fuel level gauge always displays full............................................................................................................................................................................ 757 M-19 Fuel level gauge is not displayed................................................................................................................................................................................ 759 M-20 While engine is running, service meter does not advance.......................................................................................................................................................... 761 M-21 Trouble in fuel level sensor..................................................................................................................................................................................... 762 M-22 Trouble in coolant temperature sensor............................................................................................................................................................................ 764 M-23 Wiper does not operate or operates while wiper switch is turned off.............................................................................................................................................. 765 a) Wiper does not operate (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up).................................................................................................................... 765 b) Wiper operates while wiper switch is turned off (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22832 and up)........................................................................................... 765 a) Wiper does not operate (PC78US-6 Serial No.: 6501 and up)...................................................................................................................................................... 766 b) Wiper operates while wiper switch is turned off (PC78US-6 Serial No.: 6501 and up)............................................................................................................................. 766 M-24 Washer motor does not operate or operates while washer switch is turned off...................................................................................................................................... 770 a) Washer motor does not operate.................................................................................................................................................................................. 770 b) Washer operates while wiper switch is turned off............................................................................................................................................................... 770 M-25 Depth set 0 mode and height mode cannot be selected and set (Only PC78UU-6)...................................................................................................................................... 773 30 DISASSEMBLY AND ASSEMBLY...................................................................................................................................................................................................... 775 METHOD OF USING MANUAL........................................................................................................................................................................................................ 776 PRECAUTIONS WHEN CARRYING OUT OPERATION....................................................................................................................................................................................... 777 SPECIAL TOOL LIST............................................................................................................................................................................................................. 781 COUNTERWEIGHT ASSEMBRY........................................................................................................................................................................................................ 789 REMOVAL (PC78US-2 Serial No. : 4001 – 6500 PC78UU-2 Serial No. : 22001 and up)............................................................................................................................................ 789 INSTALLATION (PC78US-2 Serial No. : 4001 – 6500 PC78UU-2 Serial No. : 22001 and up)....................................................................................................................................... 789 REMOVAL (PC78US-2 Serial No. : 6501 and up)............................................................................................................................................................................... 790 INSTALLATION (PC78US-2 Serial No. : 6501 and up).......................................................................................................................................................................... 790 INJECTION PUMP ASSEMBLY....................................................................................................................................................................................................... 791 REMOVAL (PC78US-6 Serial No.: 4001 – 5500 PC78UU-6 Serial No.: 22001 – 23500)............................................................................................................................................. 791 INSTALLATION (PC78US-6 Serial No.: 4001 • 5500 PC78UU-6 Serial No.: 22001 • 23500)........................................................................................................................................ 792 REMOVAL (PC78US-6 Serial No.: 5501 and up PC78UU-6 Serial No.: 23501 and up).............................................................................................................................................. 795 INSTALLATION (PC78US-6 Serial No.: 5501 and up PC78UU-6 Serial No.: 23501 and up)......................................................................................................................................... 796 CYLINDER HEAD ASSEMBLY........................................................................................................................................................................................................ 799 REMOVAL (PC78US-6 Serial No.: 4001 – 5500 PC78UU-6 Serial No.: 22001 – 23500)............................................................................................................................................. 799 INSTALLATION (PC78US-6 Serial No.: 4001 – 5500 PC78UU-6 Serial No.: 22001 – 23500)........................................................................................................................................ 801 REMOVAL (PC78US-6 Serial No.: 5501 and up PC78UU-6 Serial No.: 23501 and up).............................................................................................................................................. 802 INSTALLATION (PC78US-6 Serial No.: 5501 and up PC78UU-6 Serial No.: 23501 and up)......................................................................................................................................... 805 MAIN PUMP ASSEMBLY............................................................................................................................................................................................................ 807 REMOVAL................................................................................................................................................................................................................... 807 INSTALLATION.............................................................................................................................................................................................................. 808 CONTROLL PUMP ASSEMBLY........................................................................................................................................................................................................ 809 REMOVAL................................................................................................................................................................................................................... 809 INSTALLATION.............................................................................................................................................................................................................. 809 ENGINE AND MAIN PUMP ASSEMBLY................................................................................................................................................................................................. 810 REMOVAL................................................................................................................................................................................................................... 810 INSTALLATION.............................................................................................................................................................................................................. 812 ENGINE HOOD ASSEMBLY.......................................................................................................................................................................................................... 813 REMOVAL................................................................................................................................................................................................................... 813 INSTALLATION.............................................................................................................................................................................................................. 813 HYDRAULIC OIL COOLERASSEMBLY.................................................................................................................................................................................................. 815 REMOVAL (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).............................................................................................................................................. 815 INSTALLATION (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up)......................................................................................................................................... 815 REMOVAL (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................................................ 816 INSTALLATION (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................................... 816 RADIATOR ASSEMBLY............................................................................................................................................................................................................. 817 REMOVAL (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).............................................................................................................................................. 817 INSTALLATION (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up)......................................................................................................................................... 817 REMOVAL (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................................................ 818 INSTALLATION (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................................... 818 SWING MOTOR AND SWING MACHINERY ASSEMBLY...................................................................................................................................................................................... 819 REMOVAL................................................................................................................................................................................................................... 819 INSTALLATION.............................................................................................................................................................................................................. 819 SWING MACHINERY ASSEMBLY...................................................................................................................................................................................................... 820 DISASSEMBLY (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).......................................................................................................................................... 820 ASSEMBLY (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up)............................................................................................................................................. 822 DISASSEMBLY (PC78US-6 Serial No.: 6501 and up)............................................................................................................................................................................ 826 ASSEMBLY (PC78US-6 Serial No.: 6501 and up)............................................................................................................................................................................... 828 SWING MOTOR ASSEMBLY.......................................................................................................................................................................................................... 830 REMOVAL................................................................................................................................................................................................................... 830 INSTALLATION.............................................................................................................................................................................................................. 830 CENTER SWIVEL JOINT ASSEMBLY.................................................................................................................................................................................................. 831 REMOVAL................................................................................................................................................................................................................... 831 INSTALLATION.............................................................................................................................................................................................................. 831 DISASSEMBLY............................................................................................................................................................................................................... 832 ASSEMBLY.................................................................................................................................................................................................................. 832 CONTROL VALVE ASSEMBLY........................................................................................................................................................................................................ 833 REMOVAL................................................................................................................................................................................................................... 833 INSTALLATION.............................................................................................................................................................................................................. 833 ASSEMBLY.................................................................................................................................................................................................................. 834 WORK EQUIPMENT PPC VALVE ASSEMBLY............................................................................................................................................................................................. 835 ASSEMBLY.................................................................................................................................................................................................................. 835 TRAVEL PPC VALVE ASSEMBLY..................................................................................................................................................................................................... 837 ASSEMBLY.................................................................................................................................................................................................................. 837 HYDRAULIC TANK ASSEMBLY....................................................................................................................................................................................................... 838 REMOVAL (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).............................................................................................................................................. 838 INSTALLATION (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up)......................................................................................................................................... 838 REMOVAL (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................................................ 839 INSTALLATION (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................................... 840 FUEL TANK ASSEMBLY............................................................................................................................................................................................................ 841 REMOVAL (PC78US-6 Serial No.: 4001 – 4903 PC78UU-6 Serial No.: 22001 – 22788)............................................................................................................................................. 841 INSTALLATION (PC78US-6 Serial No.: 4001 – 4903 PC78UU-6 Serial No.: 22001 – 22788)........................................................................................................................................ 842 REMOVAL (PC78US-6 Serial No.: 4904 – 6500 PC78UU-6 Serial No.: 22789 and up).............................................................................................................................................. 842 INSTALLATION (PC78US-6 Serial No.: 4904 – 6500 PC78UU-6 Serial No.: 22789 and up)......................................................................................................................................... 844 REMOVAL (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................................................ 844 INSTALLATION (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................................... 845 CONTROLLER ASSEMBLY........................................................................................................................................................................................................... 845 REMOVAL (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).............................................................................................................................................. 845 INSTALLATION (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up)......................................................................................................................................... 845 INSTALLATION (PC78US-6 Serial No.: 6501 and up)........................................................................................................................................................................... 846 MONITOR PANEL ASSEMBLY........................................................................................................................................................................................................ 846 REMOVAL................................................................................................................................................................................................................... 846 INSTALLATION.............................................................................................................................................................................................................. 846 AIR CONDITIONER UNIT ASSEMBLY................................................................................................................................................................................................. 847 REMOVAL................................................................................................................................................................................................................... 847 INSTALLATION.............................................................................................................................................................................................................. 848 OPERATOR'S CAB ASSEMBLY....................................................................................................................................................................................................... 849 REMOVAL................................................................................................................................................................................................................... 849 INSTALLATION.............................................................................................................................................................................................................. 850 FLOOR FRAME ASSEMBLY.......................................................................................................................................................................................................... 851 REMOVAL................................................................................................................................................................................................................... 851 INSTALLATION.............................................................................................................................................................................................................. 852 OPERATOR’S CAB GLASS (STUCK GLASS)............................................................................................................................................................................................ 853 REMOVAL................................................................................................................................................................................................................... 854 INSTALLATION.............................................................................................................................................................................................................. 855 FRONT WINDOW ASSEMBLY......................................................................................................................................................................................................... 863 REMOVAL................................................................................................................................................................................................................... 863 INSTALLATION.............................................................................................................................................................................................................. 863 REVOLVING FRAME ASSEMBLY...................................................................................................................................................................................................... 864 REMOVAL (PC78US-6 Serial No.: 4001 – 6500 PC78UU-6 Serial No.: 22001 and up).............................................................................................................................................. 864 REMOVAL (PC78US-6 Serial No.: 6501 and up)................................................................................................................................................................................ 865 INSTALLATION.............................................................................................................................................................................................................. 866 SWING CIRCLE ASSEMBLY......................................................................................................................................................................................................... 867 REMOVAL................................................................................................................................................................................................................... 867 INSTALLATION.............................................................................................................................................................................................................. 867 WORK EQUIPMENT ASSEMBLY....................................................................................................................................................................................................... 868 REMOVAL................................................................................................................................................................................................................... 868 INSTALLATION.............................................................................................................................................................................................................. 870 REMOVAL (PC78UU-6)........................................................................................................................................................................................................ 871 INSTALLATION (PC78UU-2)................................................................................................................................................................................................... 873 FIRST BOOM ASSEMBLY........................................................................................................................................................................................................... 874 REMOVAL................................................................................................................................................................................................................... 874 INSTALLATION.............................................................................................................................................................................................................. 876 SECOND BOOM ASSEMBLY.......................................................................................................................................................................................................... 877 REMOVAL................................................................................................................................................................................................................... 877 INSTALLATION.............................................................................................................................................................................................................. 877 OFFSET BRACKET ASSEMBLY....................................................................................................................................................................................................... 878 REMOVAL................................................................................................................................................................................................................... 878 INSTALLATION.............................................................................................................................................................................................................. 879 STEEL SHOE, RUBBER PAD SHOE, ROAD LINER ASSEMBLY.............................................................................................................................................................................. 880 EXPANSION................................................................................................................................................................................................................. 880 INSTALLATION.............................................................................................................................................................................................................. 880 RUBBER SHOE ASSEMBLY.......................................................................................................................................................................................................... 881 REMOVAL................................................................................................................................................................................................................... 881 INSTALLATION.............................................................................................................................................................................................................. 881 FINAL DRIVE AND TRAVEL MOTOR ASSEMBLY......................................................................................................................................................................................... 881 REMOVAL................................................................................................................................................................................................................... 881 INSTALLATION.............................................................................................................................................................................................................. 882 TRAVEL MOTOR.................................................................................................................................................................................................................. 883 SECTIONAL DRAWING, SINGLE VIEW DRAWING.................................................................................................................................................................................... 885 1. SECTIONAL DRAWING OF ASSEMBLY...................................................................................................................................................................................... 885 2. SINGLE VIEW DISASSEMBLY DRAWING OF REDUCTION GEAR ASSEMBLY......................................................................................................................................................... 887 3. PARTS LIST......................................................................................................................................................................................................... 889 OUTLINE OF MAINTENANCE.................................................................................................................................................................................................... 892 1. TOOLS.............................................................................................................................................................................................................. 892 2. TIGHTENING TORQUE.................................................................................................................................................................................................. 897 3. WEIGHT TABLE....................................................................................................................................................................................................... 897 DISASSEMBLY............................................................................................................................................................................................................... 898 MAINTENANCE STANDARD...................................................................................................................................................................................................... 913 ASSEMBLY.................................................................................................................................................................................................................. 915 PERFORMANCE TEST.......................................................................................................................................................................................................... 932 CLEARANCE ADJUSTMENT PARTS DIMENSION TABLE................................................................................................................................................................................ 933 IDLER ASSEMBLY................................................................................................................................................................................................................ 934 ASSEMBLY.................................................................................................................................................................................................................. 934 RECOIL SPRING ASSEMBLY........................................................................................................................................................................................................ 936 DISASSEMBLY............................................................................................................................................................................................................... 936 ASSEMBLY.................................................................................................................................................................................................................. 937 TRACK ROLLER ASSEMBLY......................................................................................................................................................................................................... 938 DISASSEMBLY............................................................................................................................................................................................................... 938 ASSEMBLY.................................................................................................................................................................................................................. 939 HYDRAULIC CYLINDER ASSEMBLY................................................................................................................................................................................................... 941 DISASSEMBLY............................................................................................................................................................................................................... 941 ASSEMBLY.................................................................................................................................................................................................................. 942 50 OTHER SPECIFICATIONS.......................................................................................................................................................................................................... 945 PC78US-6 (For Norway & EU).................................................................................................................................................................................................... 947 CONTENTS...................................................................................................................................................................................................................... 948 SPECIFICATION DIMENSIONS DRAWING.......................................................................................................................................................................................... 949 WORKING RANGE DRAWING..................................................................................................................................................................................................... 950 SPECIFICATIONS............................................................................................................................................................................................................ 952 WEIGHT TABLE.............................................................................................................................................................................................................. 958 STRUCTURE, FUNCTION, AND MAINTENANCE STANDARD................................................................................................................................................................................. 960 ARRANGEMENT OF HYDRAULIC COMPONENTS....................................................................................................................................................................................... 960 SOLENOID VALVE............................................................................................................................................................................................................ 962 ACCUMULATOR FOR PPC....................................................................................................................................................................................................... 966 DIMENSIONS OF EACH PART OF WORK EQUIPMENT................................................................................................................................................................................. 968 BOOM HYDRAULIC ANTI-BURST VALVE........................................................................................................................................................................................... 970 ELECTRIC CONTROL SYSTEM................................................................................................................................................................................................... 977 GENERAL SYSTEM DIAGRAM.................................................................................................................................................................................................... 978 OVERLOAD ALARM FUNCTION................................................................................................................................................................................................... 984 OVERLOAD ALARM PRESSURE SENSOR............................................................................................................................................................................................ 985 METER DISPLAY UNIT........................................................................................................................................................................................................ 986 TROUBLESHOOTING............................................................................................................................................................................................................... 987 CONNECTOR TYPES AND MOUNTING LOCATIONS.................................................................................................................................................................................... 987 CONNECTOR ARRANGEMENT DIAGRAM............................................................................................................................................................................................. 990 EXPLANATION OF FUNCTIONS OF ELECTRIC SYSTEM CONTROL MECHANISM.............................................................................................................................................................1006 DISPLAY AND SPECIAL FUNCTIONS OF MONITOR PANEL............................................................................................................................................................................1009 TROUBLESHOOTING FOR CONTROLLER PUMP CONTROL SYSTEM (C MODE)...............................................................................................................................................................1017 PRECAUTIONS FOR TROUBLESHOOTING FOR CONTROLLER (PUMP CONTROL SYSTEM)..................................................................................................................................................1018 ACTION TAKEN BY CONTROLLER WHEN TROUBLE OCCURS AND PROBLEMS ON MACHINE................................................................................................................................................1020 JUDGEMENT TABLE FOR CONTROLLER (PUMP CONTROL SYSTEM) AND HYDRAULIC EQUIPMENT..........................................................................................................................................1024 ELECTRIC CIRCUIT DIAGRAM OF C MODE SYSTEM.............................................................................................................................................................................1028 C-1 [E232] Trouble in TVC-EPC solenoid system.........................................................................................................................................................................1031 C-2 [E233] Trouble in TVC-EPC solenoid system.........................................................................................................................................................................1031 C-3 [E203] Trouble in swing holding brake solenoid system.............................................................................................................................................................1033 C-4 [E213] Trouble in swing holding brake solenoid system.............................................................................................................................................................1033 C-5 [E206] Trouble in 2nd travel speed selection solenoid system......................................................................................................................................................1035 C-6 [E216] Trouble in 2nd travel speed selection solenoid system......................................................................................................................................................1035 C-7 [E251] Trouble in boom bottom pressure sensor (overload sensor) system............................................................................................................................................1037 C-8 [E258] short circuit in 5 V system of sensor power supply.........................................................................................................................................................1039 C-9 Work equipment still moves after work equipment lock lever is set to LOCK.........................................................................................................................................1042 C-10 Machine does not swing...........................................................................................................................................................................................1045 C-11 Travel speed does not rise.......................................................................................................................................................................................1047 C-12 Gear speed does not change automatically.........................................................................................................................................................................1048 C-13 Trouble in controller power supply (LED of controller is turned OFF).............................................................................................................................................1048 TROUBLESHOOTING FOR MACHINE MONITOR SYSTEM (M MODE).......................................................................................................................................................................1049 ELECTRIC CIRCUIT DIAGRAM OF M MODE SYSTEM.............................................................................................................................................................................1050 M-11 When starting switch is set to ON position and engine is started, basic check items flash........................................................................................................................1056 a) Alternator system (Serial No.: 4809 – 6500)....................................................................................................................................................................1056 a) Alternator system (Serial No.: 6501 and up)....................................................................................................................................................................1057 b) Engine oil pressure system (Serial No.: 4809 – 6500)...........................................................................................................................................................1058 b) Engine oil pressure system (Serial No.: 6501 and up)...........................................................................................................................................................1059 M-12 When starting switch is set to ON position (but engine is stopped), caution items and emergency stop items (excluding battery and engine oil) flash..............................................................1060 a) Alternator system (Serial No.: 4809 – 6500)....................................................................................................................................................................1060 a) Alternator system (Serial No.: 6501 and up)....................................................................................................................................................................1061 b) Engine oil pressure sensor system (Serial No.: 4809 – 6500)....................................................................................................................................................1062 b) Engine oil pressure sensor system (Serial No.: 6501 and)up)....................................................................................................................................................1063 90 OTHERS.........................................................................................................................................................................................................................1065 HYDRAULIC CIRCUIT DIAGRAM.....................................................................................................................................................................................................1067 PC78US-6 Serial No.: 4001 • 6500 (Blade-less specification)...............................................................................................................................................................1067 PC78US-6 Serial No.: 6501 and up (Blade-less specification)...............................................................................................................................................................1068 PC78US-6 (Additional attachment circuit)..................................................................................................................................................................................1069 PC78US-6 Serial No.: 4001 • 6500 (Blade specification)....................................................................................................................................................................1070 PC78US-6 Serial No.: 6501 and up (Blade specification)....................................................................................................................................................................1071 PC78US-6 Serial No.: 4809 – 6500 (Norway & EU specification)..............................................................................................................................................................1072 PC78US-6 Serial No.: 6501 and up (Norway & EU specification)..............................................................................................................................................................1073 PC78UU-6..................................................................................................................................................................................................................1074 ELECTRICAL CIRCUIT DIAGRAM....................................................................................................................................................................................................1075 PC78US-6 Serial No.: 4001 – 5500 (1/2)....................................................................................................................................................................................1075 PC78US-6 Serial No.: 4001 – 5500 (2/2)....................................................................................................................................................................................1076 PC78US-6 Serial No.: 5501 • 6500 (1/2)....................................................................................................................................................................................1077 PC78US-6Serial No.: 5501 – 6500 (2/2).....................................................................................................................................................................................1078 PC78US-6 Serial No.: 6501 and up (1/2)....................................................................................................................................................................................1079 PC78US-6 Serial No.: 6501 and up (2/2)....................................................................................................................................................................................1080 PC78US-6 Serial No.: 4809 • 5500 (Norway & EU specification) (1/2)........................................................................................................................................................1081 PC78US-6 Serial No.: 4809 – 5500 (Norway & EU specification) (2/2)........................................................................................................................................................1082 PC78US-6 Serial No.: 5501 • 6500 (Norway & EU specification) (1/2)........................................................................................................................................................1083 PC78US-6 Serial No.: 5501 – 6500 (Norway & EU specification) (2/2)........................................................................................................................................................1084 PC78US-6 Serial No.: 6501 and up (Norway & EU specification) (1/2)........................................................................................................................................................1085 PC78US-6 Serial No.: 6501 and up (Norway & EU specification) (2/2)........................................................................................................................................................1086 PC78UU-6 Serial No.: 22832 – 23500 (1/2)..................................................................................................................................................................................1087 PC78UU-6 Serial No.: 22832 – 23500 (2/2)..................................................................................................................................................................................1088 PC78UU-6 Serial No.: 23501 and up (1/2)...................................................................................................................................................................................1089 PC78UU-6 Serial No.: 23501 and up (2/2)...................................................................................................................................................................................1090
S.S 13/12/24
