Komatsu WA320-6, WA320PZ-6 Wheel Loader Service Manual
1,270 pages · Publication VEBM620100
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What's inside
From the manual's own table of contents: 56 sections, 453 entries. See sample pages (PDF, 890 KB)
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Index and foreword11 topics
- Composition of shop manual
- Safety notice
- How to read the shop manual
- Explanation of terms for maintenance standard
- Handling of electric equipment and hydraulic component
- Handling of connectors newly used for engines
- How to read electric wire code
- Precautions when carrying out operation
- Method of disassembling and connecting push-pull type coupler
- Standard tightening torque table
- Conversion table
Specification4 topics
- Specification dimension drawing
- Specifications
- Weight table
- Table of fuel, coolant and lubricants
Structure, function and maintenance standard70 topics
- Engine mount and transfer mount
- Damper
- Cooling system
- Cooling system hydraulic piping diagram
- Cooling fan motor
- Power train
- Power train system diagram
- Drive shaft
- HST hydraulic piping diagram
- HST pump
- HST motor
- Transfer
- Clutch solenoid valve
- Axle
- Differential
- Torque proportioning differential
- Limited slip differential
- Final drive
- Steering piping diagram
- Steering column
- Priority valve
- Orbit-roll valve
- Cushion valve
- Steering cylinder
- Emergency steering piping diagram
- Emergency steering valve
- Steering relief valve
- Brake piping diagram
- Charge valve
- Brake valve
- Inching valve
- Accumulator (for brake)
- Slack adjuster
- Brake
- Parking brake control
- Parking brake
- Axle mount and center hinge pin
- Tires
- Work equipment hydraulic piping diagram
- Work equipment control lever linkage
- Hydraulic tank
- 4-gear pump
- Work equipment control valve
- Cut-off valve
- PPC valve
- Lock valve
- Accumulator (for PPC circuit)
- ECSS valve
- Accumulator (for ECSS)
- Work equipment linkage
- Bucket
- Bucket positioner and boom kick-out
- Work equipment cylinder
- Air conditioner
- Machine monitor system
- Machine monitor
- Electrical system (HST controller system)
- HST controller
- ECSS system
- KOMTRAX system
- Engine starting circuit
- Engine stopping circuit
- Preheating circuit
- Engine output derating function
- Automatic warm-up function
- Parking brake circuit
- Coupler plunger control system
- Max. traction switch
- Multi-function knob
- Sensor
Standard value table2 topics
- Standard service value table for engine
- Standard service value table for chassis
Testing and adjusting57 topics
- Tools for testing, adjusting, and troubleshooting
- Measuring engine speed
- Measuring exhaust gas color
- Adjusting valve clearance
- Measuring compression pressure
- Measuring blow-by pressure
- Measuring engine oil pressure
- Measuring intake air (boost) pressure
- Handling fuel system equipment
- Releasing residual pressure in fuel system
- Measuring fuel pressure
- Measuring fuel return rate and leakage
- Bleeding air from fuel circuit
- Checking leakage in fuel system
- Handling cylinder cut-out mode operation
- Handling no-injection cranking operation
- Handling controller voltage circuit
- Check of muffler and muffler stack for looseness and damage
- Check of muffler function
- Check of installed condition of cylinder head and manifolds
- Check of engine piping for damage and looseness
- Testing and adjusting air conditioner compressor belt tension
- Replacing alternator belt
- Checking operating force of accelerator pedal
- Checking directional lever
- Testing and adjusting HST oil pressure
- Testing clutch control pressure
- Testing and adjusting steering wheel
- Testing and adjusting steering oil pressure
- Bleeding air from steering circuit
- Testing hydraulic fan
- Measuring brake pedal
- Testing and adjusting brake pedal linkage
- Measuring brake performance
- Testing and adjusting accumulator charge pressure
- Testing wheel brake oil pressure
- Testing wear of brake disc
- Bleeding air from wheel brake circuit
- Releasing residual pressure in brake accumulator circuit
- Testing parking brake performance
- Testing and adjusting parking brake control cable
- Measuring and adjusting work equipment control lever
- Testing and adjusting work equipment hydraulic pressure
- Testing work equipment PPC oil pressure
- Bleeding air from hydraulic circuit
- Releasing remaining pressure in hydraulic circuit
- Testing and adjusting bucket positioner
- Testing and adjusting of boom kick-out switch
- Checking proximity switch operation pilot lamp
- Procedure for testing diodes
- Preparation work for troubleshooting for electric system
- Starting KOMTRAX terminal operations
- Indicator lamps of KOMTRAX terminal
- Adjusting machine monitor
- Adjusting replaced, reassembled or added sensor, controller, etc. with machine monitor
- Special functions of machine monitor (EMMS)
- Pm clinic inspection chart
Troubleshooting210 topics
- Failure codes table
- Fuse locations
- Points to remember when troubleshooting
- Sequence of events in troubleshooting
- Testing before troubleshooting
- Classification and procedures of troubleshooting
- Information contained in troubleshooting table
- Connection table for connector pin numbers
- T- branch box and T- branch adapter table
- Failure code [2G40ZG] Brake: Oil pressure reduction
- Failure code [6091NX] HST filter: Clogging
- Failure code [989FN1] Travel speed: Overrun alarm
- Failure code [AA1ANX] Air cleaner: Clogging
- Failure code [AB00L6] Alternator R system: Hot short
- Failure code [AB00MA] Alternator R system: Ground fault/Disconnection/Low charge voltage
- Failure code [B@BAZG] Engine: Oil pressure reduction
- Failure code [B@BAZK] Engine oil: Low level
- Failure code [B@BCNS] Engine: Overheat
- Failure code [B@BCZK] Engine: Low coolant level
- Failure code [B@C6NS] Front brake: High oil temperature
- Failure code [B@CRNS] HST: High oil temperature
- Failure code [CA111] Abnormality in engine controller
- Failure code [CA115] Engine Ne or Bkup speed sensor error
- Failure code [CA122] Charge pressure sensor high error
- Failure code [CA123] Charge pressure sensor low error
- Failure code [CA131] Throttle sensor high error
- Failure code [CA132] Throttle sensor low error
- Failure code [CA144] Coolant sensor high error
- Failure code [CA145] Coolant sensor low error
- Failure code [CA153] Charge temperature sensor high error
- Failure code [CA154] Charge temperature sensor low error
- Failure code [CA155] Derating of speed by abnormally high charge temperature
- Failure code [CA187] Sensor power supply 2 low error
- Failure code [CA221] Atmospheric pressure sensor high error
- Failure code [CA222] Atmospheric sensor low error
- Failure code [CA227] Sensor power supply 2 high error
- Failure code [CA234] Engine overspeed
- Failure code [CA238] Ne speed sensor power supply error
- Failure code [CA271] IMV (IMA) Short circuit
- Failure code [CA272] IMV (IMA) Disconnection
- Failure code [CA322] Injector #1 open/short error
- Failure code [CA323] Injector #5 open/short error
- Failure code [CA324] Injector #3 open/short error
- Failure code [CA325] Injector #6 open/short error
- Failure code [CA331] Injector #2 open/short error
- Failure code [CA332] Injector #4 open/short error
- Table of contents Failure code [CA342] Calibration code inconsistency
- Failure code [CA351] Injectors drive circuit error
- Failure code [CA352] Sensor power supply 1 low error
- Failure code [CA386] Sensor power supply 1 high error
- Failure code [CA428] Abnormally high level in water sensor
- Failure code [CA429] Abnormally low level in water sensor
- Failure code [CA431] Idle validation switch error
- Failure code [CA432] Idle validation action error
- Failure code [CA435] Engine oil pressure switch error
- Failure code [CA441] Battery voltage low error
- Failure code [CA442] Battery voltage high error
- Failure code [CA449] Common rail pressure high error 2
- Failure code [CA451] Common rail pressure sensor high error
- Failure code [CA452] Common rail pressure sensor low error
- Failure code [CA488] Derating of torque by abnormally high charge temperature
- Failure code [CA553] Common rail pressure high error 1
- Failure code [CA559] Supply pump pressure very low error
- Failure code [CA689] Engine Ne speed sensor error
- Failure code [CA731] Engine Bkup speed sensor phase error
- Failure code [CA757] All continuous data lost error
- Failure code [CA778] Engine Bkup speed sensor error
- Failure code [CA1633] KOMNET datalink timeout error
- Failure code [CA2185] Throttle sensor supply voltage high error
- Failure code [CA2186] Throttle sensor power supply low error
- Failure code [CA2249] Supply pump pressure very low error 2
- Failure code [CA2311] Abnormality in IMV (IMA) solenoid
- Failure code [CA2555] Intake heater relay disconnection error
- Failure code [CA2556] Intake heater relay short circuit error
- Failure code [D160KY] Backup alarm/lamp relay 1 circuit: Hot short
- Failure code [D192KY] ECSS solenoid relay: Hot short
- Failure code [D1B0KA] HST safety relay: Disconnection
- Failure code [D1B0KB] HST safety relay: Ground fault
- Failure code [D1B0KY] HST safety relay: Hot short
- Failure code [D5ZHL6] IGN C system: Ground fault/Disconnection
- Failure code [DAF3KK] UNSW power supply: Ground fault/Disconnection
- Failure code [DAFRKR] Machine monitor CAN-NET Signal: Disconnection
- Failure code [DAJ0KK] HST controller power supply: Low voltage
- Failure code [DAJ0KT] HST controller memory (EEPROM): Abnormality
- Failure code [DAJ1L4] HST controller main power line: Disconnection/Ground fault
- Failure code [DAJ1L6] HST controller main power line: Hot short
- Failure code [DAJ2KK] Controller solenoid power supply: Low voltage
- Failure code [DAJ2L3] HST controller load power supply holding line: Hot short in wiring harness
- Failure code [DAJ2L4] HST controller load power supply holding line: Disconnection/Ground fault
- Failure code [DAJ5KX] Sensor 5V power supply: Out of output range
- Failure code [DAJ9KQ] HST controller model selection: Disagreement of model selection signals
- Failure code [DAJRKR] HST controller CAN-NET signal: Disconnection
- Failure code [DAJRMA] HST controller: Disagreement in option selection
- Failure code [DB2RKR] Engine controller CAN-NET: Disconnection in signal line
- Failure code [DD1NL4] Fan automatic reverse switch signal: Abnormality
- Failure code [DD1NLD] Fan reverse switch signal: Abnormality
- Failure code [DDB6KA] Parking brake reminder signal: Disconnection/Hot short
- Failure code [DDB6KB] Parking brake indicator signal: Ground fault
- (intermediate switch): Trouble
- Failure code [DDB6L0] Parking brake reminder signal: Ground fault
- Table of contents Failure code [DDB6L4] Parking brake indicator signal: Disconnection/Hot short
- Failure code [DDD7KX] Travel speed control dial signal: Disconnection/Ground fault
- Failure code [DDD7KY] Travel speed control dial signal: Hot short
- Failure code [DDE5MA] Emergency steering operation switch: Disconnection
- Failure code [DDK6KA] FNR lever: Disconnection/Ground fault
- Failure code [DDK6KY] FNR lever: Hot short
- Failure code [DDS5L6] Steering: Low oil pressure (Operation of emergency steering)
- Failure code [DF10KA] Travel speed range selector switch: Disconnection/Ground fault
- Failure code [DF10KB] Travel speed range selector switch: Hot short
- Failure code [DGH1KX] HST oil temperature sensor: Ground fault
- Failure code [DGR2KB] Brake oil temperature sensor: Ground fault
- Failure code [DGR2KZ] Brake oil temperature sensor: Disconnection/Hot short
- Failure code [DHH1KX] HST oil pressure sensor: Disconnection/Ground fault
- Failure code [DHH1KY] HST oil pressure sensor: Hot short
- Failure code [DHTCL6] HST filter clogging sensor: Functional defect
- Failure code [DJF1KA] Fuel level sensor: Disconnection/Hot short
- Failure code [DLT3KX] Travel speed sensor B: Abnormality
- Failure code [DLT4KX] Travel speed sensor A: Abnormality
- Failure code [DLT4LC] Travel speed sensor A & B: Abnormality
- Failure code [DV00KY] Alarm buzzer: Hot short
- Failure code [DW26KA] Motor 2 solenoid: Disconnection/Ground fault
- Failure code [DW26KY] Motor 2 solenoid: Hot short
- Failure code [DW7BKY] Fan reverse solenoid circuit: Hot short
- Failure code [DW7BKZ] Fan reverse solenoid circuit: Disconnection/Ground fault
- Failure code [DX16KA] Fan EPC solenoid: Disconnection
- Failure code [DX16KB] Fan EPC solenoid: Ground fault
- Failure code [DX16KY] Fan EPC solenoid: Hot short
- Failure code [DX19KA] Motor 1 solenoid: Disconnection
- Failure code [DX19KB] Motor 1 solenoid: Ground fault
- Failure code [DX19KY] Motor 1 solenoid: Hot short
- Failure code [DX20KA] Clutch EPC solenoid: Disconnection
- Failure code [DX20KB] Clutch EPC solenoid: Ground fault
- Failure code [DX20KY] Clutch EPC solenoid: Hot short
- Failure code [DXH7KB] Reverse solenoid: Ground fault
- Failure code [DXH7KZ] Reverse solenoid: Disconnection/Hot short
- Failure code [DXH8KB] Forward solenoid: Ground fault
- Failure code [DXH8KZ] Forward solenoid: Disconnection/Hot short
- Failure code [J141N1] Steering pump: Overrun alarm
- Failure code [M100N1] HST pump: Overrun alarm
- Failure code [M400N1] Motor 1: Overrun alarm
- E-1 Engine does not start
- E-2 Preheater does not operate normally
- E-3 Travel speed is low or high
- E-4 ECSS does not operate
- E-5 ECSS keeps operating
- E-6 Defective boom kick-out function and cancellation
- E-7 Defective bucket positioner function and cancellation
- E-8 Defective lift arm FLOATING holding function and cancellation
- E-9 Travel direction selection system does not function
- E-10 Fan does not reverse
- E-11 Fan keeps rotating in reverse
- E-12 Wiper does not operate
- E-13 Windshield washer does not operate
- E-14 Headlamp, clearance lamp and tail lamp do not light up or go off
- E-15 Working lamp does not light up or go off
- Table of contents E-16 Turn signal lamp and hazard lamp do not light up or go off
- E-17 Brake lamp does not light or it keeps lighting up
- E-18 Backup lamp does not light or it keeps lighting up
- E-19 Backup alarm does not sound or it keeps sounding
- E-20 Horn does not sound or it keeps sounding
- E-21 Alarm buzzer does not sound or it keeps sounding
- E-22 Air conditioner does not operate or stop
- E-23 The KOMTRAX system does not work properly
- Method of using troubleshooting chart
- Failure code and cause table
- H-1 The machine does not start
- H-2 The travel speed is slow
- H-3 The traction force is weak
- H-4 Engine stalls when traveling or engine speed drops excessively
- H-5 Shift range is not shifted
- H-6 The steering wheel does not turn
- H-7 The steering wheel is heavy
- H-8 Steering wheel shakes or jerks
- H-9 Machine deviates naturally to one side when traveling
- H-10 The brake does not work or does not work well
- H-11 The brake is not released or is dragged
- H-12 The lift arm does not rise or lower
- H-13 The lift arm moves slowly or the lift arm rising force is insufficient
- H-14 When rising, the lift arm comes to move slowly at specific height
- H-15 The lift arm cylinder cannot hold down the bucket (The bucket rises in the air)
- H-16 Hydraulic drifts of the lift arm occur often
- H-17 The lift arm wobbles during operation
- H-18 When the control lever is switched from “HOLD” to “RAISE,” the lift arm falls temporarily
- H-19 The bucket does not tilt back
- H-20 The bucket moves slowly or the tilting-back force is insufficient
- H-21 The bucket comes to operate slowly in the midst of tilting-back
- H-22 The bucket cylinder cannot hold down the bucket
- H-23 Hydraulic drifts of the bucket occur often
- H-24 The bucket wobbles during travel with load (The work equipment valve is set to “HOLD”)
- H-25 When the control lever is switched from “HOLD” to “TILT,” the bucket falls temporarily
- H-26 The control levers of the lift arm and bucket do not move smoothly and heavy
- H-27 The ECSS does not operate and machine pitches and bounces
- H-28 Fan revolution is abnormal (Fan sound/vibration is abnormally large or engine overheats)
- Method of using troubleshooting charts
- S-1 Starting performance is poor
- S-2 Engine does not start
- S-3 Engine does not pick up smoothly
- S-4 Engine stops during operations
- S-5 Engine does not rotate smoothly
- S-6 Engine lacks output (or lacks power)
- S-7 Exhaust smoke is black (incomplete combustion)
- S-8 Oil consumption is excessive (or exhaust smoke is blue)
- S-9 Oil becomes contaminated quickly
- S-10 Fuel consumption is excessive
- S-11 Oil is in coolant (or coolant spurts back or coolant level goes down)
- S-12 Oil pressure drops
- S-13 Oil level rises (Entry of coolant or fuel)
- S-14 Coolant temperature becomes too high (overheating)
- S-15 Abnormal noise is made
- S-16 Vibration is excessive
Disassembly and assembly43 topics
- How to read this manual
- Coating materials list
- Special tool list
- Sketches of special tools
- Removal and installation of fuel supply pump assembly
- Removal and installation of fuel injector assembly
- Removal and installation of cylinder head assembly
- Removal and installation of engine hood assembly
- Removal and installation of radiator
- Removal and installation of air aftercooler
- Removal and installation of hydraulic oil cooler assembly
- Removal and installation of engine assembly
- Removal and installation of engine front oil seal assembly
- Removal and installation of engine rear oil seal assembly
- Removal and installation of cooling fan and fan motor assembly
- Removal and installation of fuel tank assembly
- Removal and installation of transfer assembly
- Disassembly and assembly of transfer assembly
- Removal and installation of parking brake assembly
- Disassembly and assembly of parking brake assembly
- Removal and installation of front axle assembly
- Removal and installation of rear axle assembly
- Disassembly and assembly of axle housing assembly
- Disassembly and assembly of differential assembly
- Removal and installation of center hinge pin
- Removal and installation of counterweight assembly
- Removal and installation of HST pump and 4-gear pump assembly
- Disassembly and assembly of HST pump assembly
- Removal and installation of HST motor 1 assembly
- Removal and installation of HST motor 2 assembly
- Disassembly and assembly of HST motor assembly
- Removal and installation of work equipment control valve assembly
- Removal and installation of hydraulic tank assembly
- Disassembly and assembly of hydraulic cylinder assembly
- Removal and installation of work equipment assembly
- Removal and installation of operator's cab and floor frame assembly
- Removal and installation of operator's cab glass (Stuck glass)
- Disassembly and assembly of operator's seat assembly
- Removal and installation of air conditioner unit
- Removal and installation of monitor panel
- Removal and installation of engine controller assembly
- Removal and installation of HST controller assembly
- Removal and installation of KOMTRAX terminal assembly
Inside this manual
Real pages from this service manual (1,270 pages). Open the sample pages (PDF, 889 KB)
- Specifications, page 281: 800 Cab and its attachments
- Diagram, page 528: 200 General information on troubleshooting
- Troubleshooting, page 623: 320 Troubleshooting by failure code (Display of code), Part 2
- Foldout diagram, page 1,256: Common electrical circuit diagram (1/9)
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This is a service manual
Here's how it compares to the other manual types.
Service manual
Factory repair procedures and technical information such as specifications, troubleshooting, and wiring and hydraulic diagrams, for the models and systems the manual covers. See What's inside for its topics.
Operator's manual
Safe operation, controls, maintenance schedules, lubrication points, inspections, and basic checks. Repair procedures are in the service manual.
Parts manual
Illustrated diagrams with factory part numbers for identifying components and ordering parts. Repair procedures are in the service manual.
Engine service manuals are sometimes sold separately, since certain machine models were offered with more than one engine option.
What it's used for
Factory manual for in-house farm and construction shop use. Straightforward, complete, and easy to follow. It contains the OEM information dealership service departments and parts counters use to diagnose problems, identify components, and perform maintenance or repairs correctly.
Service shops and owner/operators who repair their own equipment
Identifying correct parts and seeing how assemblies come apart and go back together
Keeping equipment running with less downtime
Factory manual, 1,270 pages
Quantity one is the manual described above.
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Other editions and similar models
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