Hydraulic Oil Temperature Gauge Does Not Move From Minimum Or Maximum - Komatsu PC88MR-10 Shop Manual

E-16 Hydraulic oil temperature gauge does not move from minimum or
maximum
(PC88MR-FGJ-400-A-Z0-A)
1) While hydraulic oil temperature is rising normally, it does not rise from white range (C).
Failure
2) While hydraulic oil temperature is stabilized normally, it rises to red range (H).
Signal from hydraulic oil temperature sensor is input to pump controller and then data is
transmitted to machine monitor through CAN communication system.
Related
Hydraulic oil temperature can be checked with monitoring function.
information
(Code: 04401)
No. Cause
Defective hydraulic oil
temperature sensor
1
(Internal open or short
circuit)
Open and short circuit
2
in wiring harness
Open circuit in wiring
harness
3
(Wire breakage or
defective contact of
connector)
Ground fault in wiring
harness
4
(Contact with ground
circuit)
Hot short circuit in
5
wiring harness
Pump controller is
6
defective.
PC88MR-10
Procedure, measuring location, criteria, and remarks
1. Turn starting switch to OFF position.
2. Disconnect connector P22 and connect T-adapter to male side.
Between P22 (male) (1) and (2)
a Thermal characteristics of oil
Resistance
temperature sensor
Between P22 (male) (2) and ground
1. Turn starting switch to OFF position.
2. Disconnect connector CP01 and connect T-adapter to female side.
Between CP01 (female) (28) and (46)
a Resistance accords with thermal characteristics
Resistance
table in Cause 1.
Between CP01 (female) (28) and ground
a If no failure is found by check on Cause 2, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors CP01 and P22 and connect T-adapters to each
female side.
Between CP01 (female) (28) and P22 (female) (2)
Resistance
Between CP01 (female) (46) and P22 (female) (1)
a If no failure is found by check on Cause 2, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors CP01 and P22, and connect T-adapter to either
female side.
Between ground and CP01 (female) (28) or P22
Resistance
(female) (2)
1. Turn starting switch to OFF position.
2. Disconnect connector P22.
3. Insert T-adapter into connector CP01 or connect T-adapter to female side
of connector P22.
4. Turn starting switch to ON position.
Voltage Between ground and CP01 (28) or P22 (female) (2) Approx. 5 V
If no failure is found by preceding checks, pump controller is defective.
(Since this is an internal defect, troubleshooting cannot be performed.)
40 Troubleshooting
Troubleshooting of electrical system (E-mode)
10°C
30°C
80°C
100°C
Approx. 90
kz
Approx. 35
kz
Approx. 6.5
kz
Approx. 3.5
kz
Min. 1 Mz
3.5 to 90 kz
Min. 1 Mz
Max. 1 z
Max. 1 z
Min. 1 Mz
40-403