Komatsu PC88MR-10 Shop Manual page 774

40 Troubleshooting
Troubleshooting by failure code (Display of code)
No. Cause
Open or short circuit in
5
wiring harness
Open circuit in wiring
harness
6
(wire breakage or
defective contact of
connector)
40-286
Procedure, measuring location, criteria, and remarks
CAN communication line
a CAN terminating resistor of 120 z is also located in machine monitor. That
is, 2 CAN terminating resistors of 120 z are connected in parallel. When
circuit resistance is measured at connector of controller other than
machine monitor, if combined resistance is 60 z, wiring harness does not
have open circuit.
1. Turn starting switch to OFF position, and turn battery disconnect switch to
OFF position.
2. Disconnect related connectors and connect T-adapters to connectors to be
measured.
a If short circuit is found (resistance between 2 terminals is 1 z or below),
disconnect all CAN communication connectors of every controller and
check whether short circuit occurs between wiring harnesses or inside
controller.
Between CM02 (female) (8) and (9)
Between CE03 (female) (17) and (18)
Between CP01 (female) (45) and (64)
Resistance
Between AC01 (female) (9) and (10)
Between CK01 (female) (10) and (11)
Between K02 (female) (A) and (B)
ACC signal of starting switch (start of CAN communication is not
recognized)
1. Turn starting switch to OFF position, and set battery disconnect switch to
OFF position.
2. Disconnect connectors to be measured and insert T-adapters into them.
3. Turn battery disconnect switch to ON position, and turn starting switch to
ON position.
Between CM01 (10) and (3)
Between CE03 (3) and (21)
Voltage
Between AC02 (4) and (1)
Between CK02 (3) and (1)
a If no failure is found by check on cause 5, this check is not required.
1. Turn starting switch to OFF position, and set battery disconnect switch to
OFF position.
2. Disconnect related connectors and connect T-adapters to female side of
connectors to be measured.
Between CM02 (female) (8) and CP01 (female) (45)
Between CM02 (female) (9) and CP01 (female) (64)
Between CM02 (female) (8) and CE03 (female) (17)
Between CM02 (female) (9) and CE03 (female) (18)
Between CM02 (female) (8) and AC01 (female) (9)
Resistance
Between CM02 (female) (9) and AC01 (female) (10)
Between CM02 (female) (8) and CK01 (female) (10)
Between CM02 (female) (9) and CK01 (female) (11)
Between CE03 (female) (17) and K02 (female) (A)
Between CE03 (female) (18) and K02 (female) (B)
Approx. 120
z
Approx. 60
z
Approx. 60
z
Approx. 60
z
Approx. 60
z
Approx. 120
z
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
PC88MR-10