Komatsu PC200-8M0, Shop Manual

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302 Troubleshooting by failure code, Part 2
Failure code [CA452] Rail Press Sensor Low Error
40-302
34
PC200, 200LC, 220, 220LC-8M0
SEN06134-00
Failure code [CA452] Rail Press Sensor Low Error
Action
level
Failure code
Failure
Common Rail Pressure Sensor Low Error
(Engine controller system)
L03 CA452
Detail of failure q Low voltage appears in signal circuit of common rail pressure sensor.
Action of con-
troller
q
Restricts engine output and allows engine to run.
Problem on
machine
q
Engine speed or output lowers.
q
Engine does not start
Related infor-
mation
q
Signal voltage of common rail pressure sensor can be checked with monitoring function.
(Code:
36401 Common rail pressure sensor volt)
q
Method of reproducing failure code: Turn starting switch to ON position.
q
If sensor connector is disconnected even in normal condition, failure code [ CA451 ] for "High Error"
is displayed.
Cause Procedure, measuring location, criteria and remarks
1
Defective wiring harness connec-
tor
See descriptions of wiring harness and connectors in "c: Electrical equipment"
in "Checks before troubleshooting" of "General information on troubleshoot-
ing", and check them.
2
Defective common rail pressure
sensor power supply system If failure code [ CA187 ] (ground fault in sensor power supply system) or
[ CA227 ] is displayed, perform troubleshooting for it first.
3
Defective common rail pressure
sensor
a
Check that failure code [ CA187 ] (Ground fault in sensor power supply sys-
tem) is not displayed.
1. Turn starting switch to OFF position.
2. Disconnect connector FUEL RAIL PRESS.
3. Turn starting switch to ON position.
If failure code [
CA452 ] changes to [ CA451 ] , sensor is defective.
q
Reference
1. Turn starting switch to OFF position.
2. Insert T-adapters to connector ECM.
3. Turn starting switch to ON position.
Between ECM (25) and (47)
Sensor out-
put
Voltage 0.2 to 4.6 V
4
Ground fault in wiring harness
(contact with ground circuit)
1. Turn starting switch to OFF position.
2. Disconnect connectors ECM and FUEL RAIL PRESS, and connect
T-adapter to female side of ECM.
Between ECM (female) (25) and ground Resistance Min. 100 k
z
5 Short circuit in wiring harness
1. Turn starting switch to OFF position.
2. Disconnect connectors ECM and FUEL RAIL PRESS, and connect
T-adapter to female side of ECM.
Between ECM (female) (25) and (47) Resistance Min. 100 k
z
6 Defective engine controller
If no failure is found by above checks, engine controller is defective. (Since
this is an internal defect, troubleshooting cannot be performed.)