Komatsu PC200-8M0, Shop Manual

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301 Troubleshooting by failure code, Part 1
Failure code [CA131] Throttle Sensor High Error
40-301
24
PC200, 200LC, 220, 220LC-8M0
SEN06133-00
Failure code [CA131] Throttle Sensor High Error
Action
level
Failure code
Failure
Throttle Sensor High Error
(Engine controller system)
L03 CA131
Detail of failure q High voltage appears in fuel control dial circuit.
Action of con-
troller
q
Uses throttle value obtained before failure detection to run engine if failure is detected with starting
switch at ON position.
q
Uses full throttle value to run engine if starting switch is set to ON position after failure detection.
Problem on
machine
q
Engine speed cannot be controlled by using fuel control dial.
Related infor-
mation
q
Signal voltage from fuel control dial can be checked with monitoring function.
(Code: 03000 Fuel control dial voltage)
q
Method of reproducing failure code: Turn starting switch to ON position.
Cause Procedure, measuring location, criteria and remarks
1
Defective wiring harness connec-
tor
See descriptions of wiring harness and connectors in "c: Electrical equip-
ment"of "Checks before troubleshooting" in "General information on trouble-
shooting", and check them.
2
Defective throttle sensor power
supply system
If failure code [ CA2185 ] is also displayed, perform troubleshooting for it first.
3
Defective fuel control dial (throttle
sensor)
1. Turn starting switch to OFF position.
2. Disconnect connector P20 and connect T-adapters to male side.
Between P20 (male) (1) and (3) Resistance 4.0 to 6.0 k
z
Between P20 (male) (2) and (3) Resistance 0.25 to 5.0 k
z
Between P20 (male) (1) and (2) Resistance 0.25 to 5.0 k
z
4
Open or short circuit in wiring har-
ness
1. Turn starting switch to OFF position.
2. Disconnect connector CE02, and connect T-adapters to female side.
Between CE02 (famale) (22) and (23) Resistance 4.0 to 6.0 k
z
Between CE02 (famale) (9) and (23) Resistance 0.25 to 5.0 k
z
5 Short circuit in wiring harness
a
If no failure is found in checks on cause 4, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors CE02 and P20, and connect T-adapters to either
female side.
Between CE02 (female) (9) and (22), or between
P20 (female) (1) and (2)
Resistance Min. 1 M
z
6
Hot short circuit in wiring harness
(contact with 24 V circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector P20 and connect T-adapters to female side.
3. Turn starting switch to ON position.
Between P20 (female) (2) and ground Voltage Max. 1 V
7 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.)
q
Reference
1. Turn starting switch to OFF position.
2. Insert T-adapters into connector CE02.
3. Turn starting switch to ON position.
4. Operate fuel control dial and perform troubleshooting.
Between CE02 (22) and (23)
Power sup-
ply
Voltage 4.75 to 5.25V
Between CE02 (9) and (23)
Sensor out-
put
Voltage 0.5 to 4.5 V