Failure Code [Dhsjma] Travel Right Reverse Ppc Press Sensor Abnormality - Komatsu Galeo PC138US-8 Shop Manual

SEN02465-01
Failure code [DHSJMA] Travel right reverse PPC press sensor
abnormality
User code Failure code
E20 DHSJMA
Contents of
• Signal voltage of travel right reverse PPC pressure sensor circuit is below 0.3 V or above 4.5 V.
trouble
Action of
• Fixes travel right reverse PPC pressure at 0 MPa {0 kg/cm
controller
• If cause of failure disappears, system resets itself.
Problem that
• Automatic decelerator cannot be reset.
appears on
• Travel right reverse performance lowers.
machine
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.
Related
• Travel right reverse PPC pressure can be checked with monitoring function.
information
(Code: 07105 Travel right reverse PPC pressure)
• Method of reproducing failure code: Turn starting switch ON or start engine.
Defective 5V sensor power
1
supply 1 system
Defective travel right reverse
2 PPC pressure sensor (Inter-
nal defect)
Possible causes
and standard
Disconnection in wiring har-
value in normal
ness (Disconnection in wiring
3
state
or defective contact in con-
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
22
Travel right reverse PPC pressure sensor abnormality
Trouble
(Pump controller system)
Cause Standard value in normal state/Remarks on troubleshooting
If failure code [DA25KP] is also displayed, carry out troubleshoot-
ing for it first.
a Prepare with starting switch OFF, then turn starting switch ON
Between (3) – (1)
Between (2) – (1)
If voltage is abnormal, replace travel right reverse PPC pressure
sensor with another PPC pressure sensor and check failure code.
(If "E" of failure code goes off at this time, travel right reverse PPC
pressure sensor is defective.)
a Prepare with starting switch OFF, then carry out troubleshoot-
Wiring harness between C01 (female) (18)
– P26 (female) (1)
Wiring harness between C01 (female) (36)
– P26 (female) (2)
Wiring harness between C01 (female) (9) –
J07 – P26 (female) (3)
a Prepare with starting switch OFF, then carry out troubleshoot-
Wiring harness between C01 (female) (36)
– P26 (female) (2)
a Prepare with starting switch OFF, then turn starting switch ON
Wiring harness between C01 (female) (36)
– P26 (female) (2)
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.
or start engine and carry out troubleshooting in each case.
P26
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
PC138US, USLC-8
1
Max. 1 z
Max. 1 z
Max. 1 z
Min. 1 Mz
Max. 1 V