Failure Code [Ca451] Rail Press Sensor High Error - Komatsu PC200-8M0 Shop Manual

SEN06134-00

Failure code [CA451] Rail Press Sensor High Error

Action
Failure code
level
L03 CA451
q
Detail of failure High voltage appears in signal circuit of common rail pressure sensor.
Action of con-
q
Restricts engine output and allows engine to run.
troller
q
Problem on Engine speed or output lowers.
machine q Engine does not start
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.
Related infor-
q
This failure code is displayed if common rail pressure sensor connector is disconnected.
mation
q
Since troubleshooting "socket" for this sensor features female connector alone, it is not usable for
checking open circuit in wiring harness and voltage at sensor connector (not designed as a
T-adapter).
Cause
Defective wiring harness connec-
1
tor
Defective common rail pressure
2
sensor power supply system
3 Short circuit in wiring harness
Hot short circuit in wiring harness
4
(contact with 24 V circuit)
5 Open circuit in wiring harness
Defective common rail pressure
sensor
6
(improper input voltage to engine
controller)
7 Defective engine controller
*: See "Troubleshooting method for open circuit in wiring harness of pressure sensor system" of "General in-
formation on troubleshooting".
32
40-302
Common Rail Pressure Sensor High Error
Failure
(Engine controller system)
Procedure, measuring location, criteria and remarks
See descriptions of wiring harness and connectors in "c: Electrical equipment"
in "Checks before troubleshooting" of "General information on troubleshoot-
ing", and check them.
If failure code [CA227] or [CA187] is also displayed, perform troubleshooting
for it first.
1. Turn starting switch to OFF position.
2. Disconnect connectors CAM SENSOR, FUEL RAIL PRESS, BOOST
PRESS & IMT and ECM.
3. Connect T-adapters to female side of ECM.
Between ECM (female) (25) and (37)
1. Turn starting switch to OFF position.
2. Disconnect connector FUEL RAIL PRESS, and connect T-adapter to
connector ECM.
3. Turn starting switch to ON position (with connector FUEL RAIL PRESS
disconnected).
a Pin (25) of ECM is connected to 5V line via resistor inside engine controller.
Between ECM (25) and (47)
If no failure is found by above checks, there may be open circuit in wiring har-
ness. (*)
a If no failure is found by checks on causes 1 to 5 and check result of cause
6 is abnormal, sensor is defective.
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)
If no failure is found by above checks, engine controller is defective. (Since
this is an internal defect, troubleshooting cannot be performed.)
302 Troubleshooting by failure code, Part 2

Failure code [CA451] Rail Press Sensor High Error

Resistance Min. 100 kz
Sensor out-
put
PC200, 200LC, 220, 220LC-8M0
Voltage Approx. 5 V
Voltage 0.2 to 4.6 V