Komatsu Galeo PC850-8 User Manual

18 PC800, 850-8
SEN00792-02 40 Troubleshooting
Failure code [DHPFKB] R Pump P. Sensor S/C
Action code Failure code
Trouble
R Pump P. Sensor S/C
(Pump controller system)
— DHPFKB
Contents of
trouble
• Signal voltage from the front pump pressure sensor is below 0.3 V or above 4.42 V.
Action of
controller
• Fixes travel speed to Lo.
• Continues controls, assuming pressure to be constant {350 kg/cm
2
}.
• Even if cause of failure disappears, system does not reset itself until starting switch is turned OFF.
Problem that
appears on
machine
• Front pump pressure cannot be monitored.
• Travel speed and work equipment speed do not rise.
Related
information
• Input from the rear pump pressure sensor (pressure) can be checked in the monitoring function.
(Code No. 01101: Rear pump 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
Sensor power supply sys-
tem defective
If failure code [DA25KP] is displayed, carry out troubleshooting for it
first.
2
Rear pump pressure
sensor defective
(Internal defect)
aTurn the engine starting switch OFF for the preparations, and turn to
ON or keep the engine running during the troubleshooting.
P26 Voltage
Between (3) – (1) Power supply 4.5 – 5.5 V
Between (2) – (1) Signal 0.5 – 4.5 V
The pressure sensor voltage is measured with the wiring harness con-
nected. Accordingly, if the voltage is abnormal, check the wiring harness
and controller, too, for another cause of the trouble, and then judge.
3
Disconnection of wiring har-
ness
(Disconnection or defective
contact with connector)
aTurn the engine starting switch OFF for the preparations, and hold it in
the OFF position during the troubleshooting.
Between wiring harness between CP01
(female) (2) – P26 (female) (2) – P26 grounding
Resistance Min. 1 Mz
4
Short-circuiting of wiring
harness
(Contact with 24 V circuit)
aTurn the engine starting switch OFF for the preparations, and hold it in
the ON position during the troubleshooting.
Between wiring harness between CP01
(female) (22) – J21 – P26 (female) (3) and
grounding
Voltage Max. 1 V
Between wiring harness between CP01
(female) (2) – P26 (female) (2) and grounding
Voltage Max. 1 V
5 Pump controller defective
aIf causes 1 – 4 are not detected, pump may be defective. (Since trou-
ble is in system, troubleshooting cannot be carried out.)

Komatsu Galeo PC850-8 Specifications

General

Brand	Komatsu
Model	Galeo PC850-8
Category	Excavators
Language	English