Komatsu PC200-8M0, Shop Manual, Page: 606 / 1254

301 Troubleshooting by failure code, Part 1
Failure code [CA155] Chg Air Temp High Speed Derate
40-301
36
PC200, 200LC, 220, 220LC-8M0
SEN06133-00
Failure code [CA155] Chg Air Temp High Speed Derate
Action
level
Failure code
Failure
Charge Air Temperature High Speed Derate
(Engine controller system)
L03 CA155
Detail of failure
q
Boost temperature sensed by charge (boost) pressure & temperature sensor exceeds upper limit
of temperature control.
Action of con-
troller
q
Restricts engine output and allows engine to run.
Problem on
machine
q
Engine output lowers.
q
Engine stops.
Related infor-
mation
q Boost temperature can be checked with monitoring function.
(Code: 18500 Boost temperature)
q Method of reproducing failure code: Start engine.
Cause Procedure, measuring location, criteria and remarks
1
Lowered cooling performance of
aftercooler
Aftercooler cooling performance may degrade. Check it for following points:
q
Looseness and damage of fan belt
q Insufficient cooling air
q
Clogging of aftercooler fins
2
Abnormal rise of turbocharger out-
let temperature Outlet temperature of turbocharger may be abnormally high. Check related
parts.
3
Defective boost temperature sen-
sor If no failure is found by above checks, boost temperature sensor system may
be defective. Perform troubleshooting for failure codes [
CA153 ] and [ CA154 ].