Komatsu PC130-7, Shop Manual

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20-344
PC130-7
TROUBLESHOOTING
Error code [227] (Abnormality in engine speed sensor)
User code Error code
Trouble
Abnormality in engine speed sensor
(Governor and pump controller system)
– 227
Contents of
trouble
• Normal pulse signals are not input to the signal circuit of the engine speed sensor.
Action of
controller
• Controls as if in the E-mode.
• If the cause of the failure disappears, the system resets itself.
Problem that
appears on
machine
• The output power is a little low (The engine speed cannot be sensed).
Related
information
• The input state (ON/OFF) from the engine speed sensor can be checked with the monitoring function.
(Code: 010, by 10 rpm)
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Defective engine speed
sensor (Internal short cir-
cuit or disconnection)
a
Prepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
E04 (male) Resistance
Between (1) and (2) 500 – 1,000
z
Between (1) and chassis ground Min. 1 M
z
2
Defective adjustment of
engine speed sensor
See TESTING AND ADJUSTING, Adjusting engine speed sensor.
3
Disconnection in wiring
harness (Disconnection in
wiring harness or defective
contact in connector)
a
Prepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
Wiring harness between C01 (female) (40) and
E04 (female) (1)
Resistance Max. 1
z
Wiring harness between C01 (female) (29),
(39) and E04 (female) (2)
Resistance
Max. 1
z
4
Short circuit with power
source in wiring harness
(Contact with 24-V circuit)
a
Prepare with starting switch OFF, then turn starting switch ON and car-
ry out troubleshooting.
Between C01 (female) (40) – E04 (female) (1)
wiring harness and chassis ground
Voltage Max. 1 V
5
Defective governor and
pump controller
a
Prepare with starting switch OFF, then carry out troubleshooting with-
out turning starting switch.
C02 Resistance
Between (40) and (29), (39) 500 – 1,000
z
Between (40) and chassis ground Min. 1 M
z
[227]
(1)