Code [238/Ca238] Ne Speed Sensor Sup. Volt. Error - Komatsu 114E-3 Series Shop Manual

SEN00459-01
E-17 Code [238/CA238] Ne Speed Sensor Sup. Volt. Error
Error code Failure code
238
Contents of
• Low voltage is detected in engine Ne speed sensor power supply circuit.
trouble
Action of
• Controls Ne speed sensor with signals of Bkup speed sensor.
controller
Problem that
• Starting performance is poor
appears
• There is hunting from engine.
on machine
Related infor-
• Method of reproducing failure code: Starting switch ON.
mation
Defective sensor or wiring
1
Possible harness
causes and
standard value
in normal state
Defective wiring harness
2
connector
Circuit diagram related to engine Ne speed sensor
30
Trouble
CA238
Causes
Abnormality in Ne speed sensor power supply
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
right in order.
Ne speed sensor
If mark E of failure
code disappears after
reproduction opera-
tion is conducted, that
device or wiring
harness 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
40 Troubleshooting
CRANK SENSOR
Engine wiring
harness
114E-3 Series
1
J1