Komatsu PC88MR-10 Shop Manual page 869

No. Cause
Open circuit in wiring
harness
19
(Wire breakage or
defective contact of
connector)
PC88MR-10
Procedure, measuring location, criteria, and remarks
Battery relay
1. Turn starting switch to OFF position.
Between terminal R02 and D01 (female) (1)
Resistance
Between D01 (female) (5) and H15 (female) (2)
Battery relay
1. Turn starting switch to OFF position.
2. Turn starting switch to ON position.
a Check where 24 V power is reached to, and locate open section.
Between terminals R04 and R01
Between terminals R02 and R01
Voltage
Between terminals R03 and R01
Between terminal R01 and ground
Alternator and starting motor
1. Turn starting switch to OFF position.
2. Turn battery disconnect switch to OFF position.
3. Insert T-adapters into connectors H15, S14, R07, and E12.
4. Turn battery disconnect switch to ON position.
5. Turn starting switch to START position to perform troubleshooting.
a Check where 24 V power is reached to, and locate open section.
Between H15 (4) and ground
Between S14 (1) and ground
Between S14 (3) and ground
Voltage Between R07 (4) and ground
Between E12 (1) and ground
Between alternator terminal B and ground
Between starting motor terminal B and ground
If fuse or fusible link is burnt out, replace it with new one.
1. Turn starting switch to OFF position.
2. Disconnect connectors H15, S14, R06, R07, and CM01.
3. Connect T-adapters to female sides of H15, R06, R07, CM01 and to male
side of S14.
4. Remove fuse F01-3.
Between H15 (female) (4) and R06 (female) (3)
Between R06 (female) (5) and R07 (female) (3)
Between R07 (female) (1) and S14 (male) (1)
Between R07 (female) (2) and CM01 (female) (6)
Between R07 (female) (4) and starting motor safety
relay terminal S
Between alternator terminal B and starting motor
Resistance
terminal B
Between alternator terminal R and starting motor
safety relay terminal R
Between alternator terminal R and D01 (female) (6)
Between F01-3 and S14 (male) (1)
Between S14 (male) (3) and R06 (female) (1)
Between R06 (female) (2) and ground (T05)
40 Troubleshooting
Troubleshooting of electrical system (E-mode)
Max. 1 z
Max. 1 z
20 to 30 V
20 to 30 V
20 to 30 V
Max. 1 V
20 to 30 V
20 to 30 V
20 to 30 V
20 to 30 V
20 to 30 V
20 to 30 V
20 to 30 V
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
40-381