Komatsu PC210-8, Shop Manual

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UEN00242-01 40 Troubleshooting
20
PC210, 230, 240-8
Failure code [DHS8MA] Boom Raise PPC Press Sensor Abnormality 1
User code Failure code
Trouble
Boom raise PPC pressure sensor abnormality
(Pump controller system)
— DHS8MA
Contents of
trouble
• Signal voltage of boom raise PPC pressure sensor circuit is below 0.3 V or above 4.5 V.
Action of
controller
• Fixes boom raise PPC pressure at 0 MPa {0 kg/cm
2
} and continues control.
• If cause of failure disappears, system resets itself.
Problem that
appears on
machine
• Automatic decelerator cannot be reset.
• Boom raise performance lowers.
Related infor-
mation
a
If 5V circuit (3) and ground circuit (1) of pressure sensor are connected inversely, pressure sensor
will be broken. Accordingly, take extreme care when checking.
• Boom raise PPC pressure can be checked with monitoring function.
(Code: 07400 Boom raise PPC pressure)
• Method of reproducing failure code: Turn starting switch ON or start engine.
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Defective 5V sensor power
supply 1 system If failure code [ DA25KP ] is also displayed, carry out troubleshooting
for it first.
2
Defective boom raise PPC
pressure sensor (Internal
defect)
a
Prepare with starting switch OFF, then turn starting switch ON or
start engine and carry out troubleshooting in each case.
P06 Voltage
Between (3) – (1) Power supply 4.5 – 5.5 V
Between (2) – (1) Signal 0.3 – 4.5 V
If voltage is abnormal, replace boom raise PPC pressure sensor
with another PPC pressure sensor and check failure code. (If "E" of
failure code goes off at this time, boom raise PPC pressure sensor
is defective.)
3
Disconnection in wiring har-
ness (Disconnection in wiring
or defective contact in con-
nector)
a
Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between C01 (female) (18) –
P06 (female) (1) Resis-
tance
Max. 1
z
Wiring harness between C01 (female) (53) –
P06 (female) (2) Resis-
tance
Max. 1
z
Wiring harness between C01 (female) (9) –
J06 – P06 (female) (3) Resis-
tance
Max. 1
z
4
Ground fault in wiring har-
ness (Short circuit with GND
circuit)
a
Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between C01 (female) (53) –
P06 (female) (2) Resis-
tance
Min. 1 M
z
5
Hot short (Short circuit with
24V circuit) in wiring harness
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
Wiring harness between C01 (female) (53) –
P06 (female) (2)
Voltage Max. 1 V
6 Defective pump controller
If causes 1 – 5 are not detected, pump controller may be defective.
(Since trouble is in system, troubleshooting cannot be carried out.)