Komatsu PC88MR-10 Shop Manual page 867

No. Cause
Defective fusible link
9
F02
Open circuit 1 in wiring
harness
10
(Wire breakage or
defective contact of
connector)
Ground fault 1 in wiring
harness
11
(contact with ground
circuit)
Defective starting
switch
12
(Internal open circuit)
Defective lock lever
switch
13
(Internal open circuit)
Defective starting motor
14
cut-off relay
PC88MR-10
Procedure, measuring location, criteria, and remarks
a If no failure is found by check on Cause 7, this check is not required.
If fusible link is burnt out, circuit may have ground fault. In this case,
perform troubleshooting for Cause 11 first.
Fuses No. 1 to 13 are connected to fusible link F02.
a Connected circuit is large in scale. Accordingly, if no failure is found by
check on Cause 11, reproduce trouble and find out ground fault position by
sound and burning smell.
a If no failure is found by check on Cause 7, this check is not required.
1. Turn starting switch to OFF position, and turn battery disconnect switch to
OFF position.
(To prevent short circuit during troubleshooting)
2. Disconnect fusible link F02 and fuse No. 3 of fuse box F01.
3. Connect T-adapter to male side of connector F02.
Between battery relay (R03) and F02 (male) (1)
Resistance
Between F02 (male) (2) and F01-1A
a If no failure is found by check on Cause 7, this check is not required.
1. Turn starting switch to OFF position, and turn battery disconnect switch to
OFF position.
2. Disconnect fusible link F02, fuse No. 3 of fuse box F01, and battery relay
R03 (M terminal).
3. Connect T-adapter to male side of connector F02.
Between ground and battery relay R03 (harness
side) or F02 (male) (1)
Resistance
Between ground and F02 (male) (2) or F01-1A
a If no failure is found by check on Cause 8, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connector H15 and connect T-adapter to male side.
3. After troubleshooting, turn starting switch to ON and START positions to
perform troubleshooting again.
Between H15 (male) (1)
and (2)
Between H15 (male) (1)
Resistance
and (5)
Between H15 (male) (1)
and (4)
a If no failure is found by check on Cause 8, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connector S14 and connect T-adapter to female side.
Between S14 (female)
Resistance
(1) and (3)
a If no failure is found by check on Cause 8, this check is not required.
a Before performing troubleshooting, check that the head lamp lights up.
1. Turn starting switch to OFF position.
2. Interchange starting motor cut-off relay (R06) with light relay (R05).
3. Start engine.
If engine starts, original starting motor cut-off relay is defective.
40 Troubleshooting
Troubleshooting of electrical system (E-mode)
Turn starting switch to
OFF position.
Turn starting switch to
ON position.
Turn starting switch to
OFF position.
Turn starting switch to
ON position.
Turn starting switch to
OFF position.
Turn starting switch to
START position.
Lock lever: FREE
Lock lever: LOCK
Max. 1 z
Max. 1 z
Min. 1 Mz
Min. 1 Mz
Min. 1 Mz
Max. 1 z
Min. 1 Mz
Max. 1 z
Min. 1 Mz
Max. 1 z
Min. 1 Mz
Max. 1 z
40-379