Komatsu PC200-8M0, Shop Manual

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301 Troubleshooting by failure code, Part 1
Failure code [CA153] Chg Air Temp Sensor High Error
40-301
32
PC200, 200LC, 220, 220LC-8M0
SEN06133-00
Failure code [CA153] Chg Air Temp Sensor High Error
Action
level
Failure code
Failure
Charge Air Temperature Sensor High Error
(Engine controller system)
L03 CA153
Detail of failure
q
High voltage appears in temperature signal circuit of charge (boost) pressure & temperature sen-
sor.
Action of con-
troller
q
Takes boost temperature to be at fixed value and allows engine to run.
Problem on
machine
q
Engine protection function based on boost temperature does not work.
Related infor-
mation
q
Input voltage from boost temperature sensor can be checked with monitoring function.
(Code:
18501 (V) )
q
Temperature sensed by boost temperature sensor can be checked with monitoring function.
(Code:
18500(°C ))
q
Method of reproducing failure code: Turn starting switch to ON position.
q
Because troubleshooting "socket" for this sensor features female connector alone, it is not connect-
able to female connector of sensor wiring harness, and thus not usable for checking open circuit
(not designed as a T-adapter).
q
This failure code is displayed if temperature sensor connector is disconnected.
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 charge temperature sen-
sor
1. Turn starting switch to OFF position.
2. Disconnect connector BOOST PRESS & IMT, and connect socket to male
side.
Between BOOST
PRESS & IMT (male) (3)
and (4)
a
Boost tempera-
ture-Resistance cha-
riacteristic
-40 °C Resistance 41 to 48 k
z
-20 °C Resistance 14 to 16 k
z
0 °C Resistance 5.4 to 6.1 k
z
30 °C Resistance 1.6 to 1.8 k
z
60 °C Resistance 560 to 600
z
90 °C Resistance 230 to 250
z
130 °C Resistance 80 to 90
z
3
Open or short circuit in wiring har-
ness
1. Turn starting switch to OFF position.
2. Disconnect connector ECM and connect T-adapters to female side.
Between ECM (female) (23) and (47)
a
Use "Boost temperature-Resistance character-
istics" table shown above as resistance criteria.
Resis-
tance
80
z
to 48 k
z
4 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.)