Komatsu PC200-8M0, Shop Manual, Page: 848 / 1254

400 Troubleshooting of electrical system (E-mode)
E-8 Engine coolant temperature gauge does not indicate properly
40-400
26
PC200, 200LC, 220, 220LC-8M0
SEN06138-00
E-8 Engine coolant temperature gauge does not indicate properly
Engine coolant temperature gauge and coolant
temperature monitor
Failure
1) While engine coolant temperature is rising properly, temperature gauge indicator does not rise
above white range (C).
2) While engine coolant temperature remains in normal range, temperature gauge indicator rises to
red range (H).
Related infor-
mation
q Signal voltage of engine coolant temperature sensor is input to engine controller and then data is
transmitted to machine monitor through CAN communication system.
q Engine coolant temperature can be checked with monitoring function
(Code: 04107 Engine coolant temperature)
Cause Procedure, measuring location, criteria and remarks
1
Defective engine coolant
temperature sensor system Engine coolant temperature sensor system may be defective. Perform troubleshoot-
ing for failure codes [
CA144 ] and [ CA145 ].
2 Defective machine monitor
If no failure is found by check on cause 1, machine monitor may be defective.
(Since this is an internal defect, troubleshooting cannot be performed.)
Failure
3) Indication of engine coolant temperature gauge is different from actual engine coolant tempera-
ture.
4) Indication of engine coolant temperature gauge is different from display of engine coolant temper-
ature monitor.
Related infor-
mation
q
Signal voltage of engine coolant temperature sensor is input to engine controller and then data is
transmitted to machine monitor through CAN communication system.
q
Engine coolant temperature can be checked with monitoring function
(Code: 04107 Engine coolant temperature)
Cause Procedure, measuring location, criteria and remarks
1 Defective machine monitor
a
Turn starting switch to ON position or start engine and perform troubleshooting.
Engine coolant tempera-
ture
Coolant temperature
gauge level
Color of monitor light (a)
105 °C 6
Red
102 °C 5
100°C 4
Blue 85 °C 3
60 °C 2
30°C 1 White