Komatsu WA250PT-5H, Operation & Maintenance Manual

Page: 170 / 255

Troubleshooting
OPERATION
Other trouble
3-112
Other trouble 0.
Electrical system 0.
( ): Always contact your Komatsu distributor when dealing with these items.
In cases of abnormalities or causes which are not listed below, please contact your Komatsu distributor for
repairs.
Problem Main causes Remedy
Lamp does not glow brightly even
when the engine runs at high
speed
Lamp flickers while engine is run-
ning
•Defective wiring
•Defective adjustment of belt ten-
sion
(•Check, repair loose terminals,
disconnections)
•Check, Adjust fan belt tension
For details, see "Every 1000
hours service on page 4-50".
Even when the engine is rotating,
the charge caution pilot lamp does
not go out •Defective alternator
•Defective wiring
•Defective adjustment of fan belt
tension (•Replace)
(•Check, repair)
•Check, Adjust fan belt tension
For details, see "Every 1000
hours service on page 4-50".
Abnormal noise is generated from
alternator •Defective alternator (•Replace)
Starting motor does not turn when
starting switch is turned to ON •Defective wiring
•Insufficient battery charge
•Defective starting motor (•Check, repair)
•Charge
(•Check, repair)
Pinion of starting motor keeps
going in and out •Insufficient battery charge •Charge
Starting motor turns engine slug-
gishly •Insufficient battery charge
•Defective starting motor •Charge
(•Replace)
Starting motor disengages before
engine starts •Defective wiring
•Insufficient battery charge (•Check, repair)
•Charge
Preheating pilot lamp does not
light up
•Defective wiring
•Defective heater relay, preheating
water temperature sensor
•Defective preheating pilot lamp
(•Check, repair)
(•Replace)
(•Replace)
Even when engine is stopped,
charge caution pilot lamp does not
light up (starting switch at ON
position) •Defective wiring
•Defective monitor (•Check, repair)
(•Replace)
Even when engine is stopped,
engine oil pressure caution pilot
lamp does not light up (starting
switch at ON position) •Defective pilot lamp
•Defective pilot lamp switch
•Defective monitor (•Replace)
(•Replace)
(•Replace)