Code [187/Ca187] Sensor Sup. 2 Volt. Low Error - Komatsu 114E-3 Series Shop Manual

SEN00459-01
E-12 Code [187/CA187] Sensor Sup. 2 Volt. Low Error
Error code Failure code
187
Contents of
• Low voltage is detected in sensor power supply 2 circuit.
trouble
Action of con- • Fixes charge pressure and charge temperature, and continues operation.
troller • Limits output and continues operation.
Problem that
appears on • Engine output drops.
machine
Related infor-
• Method of reproducing failure code: Starting switch ON.
mation
Defective sensor or wiring
1
harness
Possible causes
and standard
value in normal
state
Defective wiring harness
2
connector
3 Defective engine controller
22
Trouble
CA187
Causes
Abnormally low level in sensor power supply 2
Standard value in normal state/Remarks on troubleshooting
a Disconnect connector with starting switch OFF, then turn starting
switch ON and carry out troubleshooting.
Disconnect devices at Boost pressure, tem-
right in order. If mark
E of failure code dis-
Common rail pres-
appears after repro-
duction operation is
conducted, that
device or wiring har-
ness has a defect in
it.
Connecting parts among each sensor, engine wiring harness, and
engine controller are suspected. Inspect them directly.
• Loose connector, broken lock, broken seal
• Corrosive, bent, broken, forced-in, or extended pin
• Humidity in connector, entry of dirt or dust, poor insulation
If causes 1 and 2 are not detected, engine controller may be defec-
tive. (Since trouble is in system, troubleshooting cannot be carried
out.)
40 Troubleshooting
BOOST PRESS &
perature sensor
FUEL RAIL PRESS
sure sensor
Bkup sensor CAM SENSOR
Engine wiring
harness
114E-3 Series
1
IMT
J1