Komatsu WA380-6 Shop Manual page 14

SEN00778-03
Table of failure modes and causes ..........................................................................................
H-1 The machine does not start .............................................................................................. 10
H-2 Torque converter lockup is not switched off (engine stalls)
[Machine with lockup clutch (if equipped)]........................................................................ 12
H-3 Torque converter lockup is not switched on [Machine with lockup clutch (if equipped)] ... 13
H-4 The travel speed is slow, the thrusting force is weak, the uphill traveling power is weak,
and the gear is not shifted ................................................................................................ 14
H-5 Shocks are large at the times of starting and shifting gear ............................................... 16
H-6 Time lag is large at the times of starting and shifting gear ................................................ 18
H-7 The torque converter oil temperature is high .................................................................... 20
H-8 Steering does not turn....................................................................................................... 21
H-9 Steering does not turn [Machine with joystick steering (if equipped)] ............................... 22
H-10 Steering response is low ................................................................................................. 23
H-11 Turning, response of steering is poor [machine with joystick steering (if equipped)] ...... 24
H-12 Steering is heavy............................................................................................................. 25
H-13 When machine turns, it shakes or makes large shocks.................................................. 26
H-14 When machine turns, it shakes or makes large shocks
[machine with joystick steering (if equipped)] ................................................................... 27
H-15 The wheel brake does not work or does not work well ................................................... 28
H-16 The wheel brake is not released or it drags .................................................................... 29
H-17 The parking brake does not work or does not work well................................................. 30
H-18 The parking brake is not released or it drags (including emergency release system) .... 31
H-19 Lift arm does not rise ...................................................................................................... 32
H-20 Lift arm speed is low or rising force of lift arm is insufficient ........................................... 33
H-21 When rising, the lift arm comes to move slowly at specific height .................................. 34
H-22 The lift arm cylinder cannot hold down the bucket (Bucket floats) .................................. 34
H-23 Hydraulic drifts of the lift arm is large .............................................................................. 34
H-24 The lift arm wobbles during operation............................................................................. 34
H-25 Bucket does not tilt back ................................................................................................. 35
H-26 Bucket speed is low or tilting back force is insufficient ................................................... 36
H-27 The bucket comes to operate slowly in the midst of tilting-back ..................................... 37
H-28 The bucket cylinder cannot hold down the bucket .......................................................... 37
H-29 Hydraulic drifts of the bucket is large .............................................................................. 37
H-30 The bucket wobbles during travel with cargo (The work equipment valve is
set to "HOLD") .................................................................................................................. 37
H-31 Lift arm and bucket control levers do not move smoothly and are heavy ....................... 38
H-32 During operation of the machine, engine speed lowers remarkably or engine stalls ...... 39
H-33 Large shock is made when work equipment starts and stops......................................... 39
H-34 When work equipment circuit is relieved singly, other work equipment moves .............. 39
H-35 ECSS does not operate, and pitching, bouncing occur .................................................. 40
Troubleshooting of engine (S-mode)
Troubleshooting of engine (S-mode) ...........................................................................................
Method of using troubleshooting chart.....................................................................................
S-1 Engine does not start easily. .............................................................................................
S-2 Engine does not start ........................................................................................................
S-3 Engine does not pick up smoothly .................................................................................... 10
S-4 Engine stops during operations......................................................................................... 11
S-5 Engine does not rotate smoothly....................................................................................... 12
S-6 Engine lacks output (or lacks power) ................................................................................ 13
S-7 Exhaust smoke is black (Incomplete combustion) ............................................................ 14
S-8 Oil consumption is excessive (or exhaust smoke is blue)................................................. 15
S-9 Engine oil becomes contaminated quickly ........................................................................ 16
S-10 Fuel consumption is excessive ....................................................................................... 17
S-11 Coolant contains oil (blows back or reduces) .................................................................. 18
S-12 Oil pressure drops........................................................................................................... 19
S-13 Oil level rises (Water, fuel in oil) ...................................................................................... 20
S-14 Coolant temperature rises too high (Overheating) .......................................................... 21
S-15 Abnormal noise is made.................................................................................................. 22
12
00 Index and foreword
6
SEN01243-00
3
3
6
7
WA380-6 (KA SPEC.)