Failure Code [Ca2556] Grid Htr Relay Volt High Error - Komatsu ecot3 PC300LC-8 Shop Manual

SEN02630-05

Failure code [CA2556] Grid Htr Relay Volt High Error

Action code Failure code
E15 CA2556
Contents of
• Short circuit was detected in drive circuit of intake air heater relay.
trouble
Action of con-
• None in particular.
troller
Problem that
• Intake air heater does not work (Engine does not start easily and exhaust gas becomes white at low
appears on
temperature).
machine
Related infor- • Method of reproducing failure code: Turn starting switch ON when engine coolant temperature is
mation below –4°C.
Defective automatic pre-
1
heater relay
Short circuit in wiring har-
Possible causes
2 ness
and standard
(with another wiring harness)
value in normal
state
Short circuit in wiring har-
3 ness
(with another wiring harness)
Defective wiring harness
4
connector
5 Defective engine controller
54
Grid heater relay volt high error
Trouble
(Engine controller system)
Cause Standard value in normal state/Remarks on troubleshooting
a
a
Replace automatic preheater relay (R18) with another relay and
perform reproducing operation. If "E" of failure code goes off at this
time, replaced relay is defective.
a
Between CE02 (female) (40) – each of CE02
(female) pins (With R18 disconnected)
a
Between CE02 (female) (40) – each of CE02
(female) pins (With R18 disconnected)
Connecting parts between automatic preheater relay – machine wir-
ing harness – engine controller may be defective. Check them
directly.
• Looseness of connector, breakage of lock, or breakage of seal
• Corrosion, bend, breakage, push-in, or expansion of pin
• Moisture or dirt in connector or defective insulation
a
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON. (Troubleshooting for
relay unit)
R18 (male)
Between (1) – (2)
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting. (Troubleshooting by replace-
ment)
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
Prepare with starting switch OFF, then carry out troubleshoot-
ing without turning starting switch ON.
CE02 (female)
Between (40) – (42)
40 Troubleshooting
1
Resistance
300 – 600 z
Resis- Min.
tance 100 kz
Resis- Min.
tance 100 kz
Resistance
300 – 600 z
PC300, 350-8