Failure Code [Dhpama] Pump Press Sensor Abnormality - Komatsu PC130-8 Shop Manual

SEN04121-02

Failure code [DHPAMA] Pump press sensor abnormality

User code Failure code
— DHPAMA
Contents of
• Signal voltage of pump pressure sensor circuit is below 0.3 V or above 4.4 V.
trouble
Action of
• Fixes pump pressure at 0 MPa {0 kg/cm
controller
• If cause of failure disappears, system resets itself.
Problem that
• Automatic gear shifting function does not work.
appears on
• Straight travel performance or steering performance lowers.
machine
a If 5V circuit (3) and ground circuit (1) of pressure sensor are connected inversely, pressure sensor
Related will be broken. Accordingly, take extreme care when checking.
information • Pump pressure can be checked with monitoring function. (Code: 01100 Pump pressure)
• Method of reproducing failure code: Turn starting switch ON or start engine.
Defective 5V sensor power
1
supply 1 system
Defective pump pressure
2
sensor (Internal defect)
Possible causes
Disconnection in wiring har-
and standard
ness (Disconnection in wiring
3
value in normal
or defective contact in con-
state
nector)
Ground fault in wiring har-
4 ness (Short circuit with GND
circuit)
Hot short (Short circuit with
5
24V circuit) in wiring harness
6 Defective pump controller
14
Pump pressure sensor abnormality
Trouble
(Pump controller system)
Cause Standard value in normal state/Remarks on troubleshooting
a If failure code [DA25KP] is also displayed, carry out trouble-
a Prepare with starting switch OFF, then turn starting switch ON
Between (3) – (1)
Between (2) – (1)
If voltage is abnormal, check failure code. (If "E" of failure code
goes off at this time, pump pressure sensor is defective.)
a Prepare with starting switch OFF, then carry out troubleshoot-
Wiring harness between CP01 (female) (18)
– P25 (female) (1)
Wiring harness between CP01 (female) (49)
– P25 (female) (2)
Wiring harness between CP01 (female) (9)
– P25 (female) (3)
a Prepare with starting switch OFF, then carry out troubleshoot-
Wiring harness between CP01 (female) (49)
– P25 (female) (2) and chassis ground
a Prepare with starting switch OFF, then turn starting switch ON
Wiring harness between CP01 (female) (49)
– P25 (female) (2) and chassis ground
If causes 1 – 5 are not detected, pump controller may be defective.
(Since trouble is in system, troubleshooting cannot be carried out.)
2
} and continues control.
shooting for it first.
or start engine and carry out troubleshooting in each case.
P25
Power supply
ing without turning starting switch ON.
ing without turning starting switch ON.
and carry out troubleshooting.
40 Troubleshooting
Voltage
4.5 – 5.5 V
Signal 0.3 – 4.5 V
Resis-
tance
Resis-
tance
Resis-
tance
Resis-
tance
Voltage
1
Max. 1 z
Max. 1 z
Max. 1 z
Min. 1 Mz
Max. 1 V
PC130-8