Failure Code [Dxa8Ka] Front Pump Pc-Epc Solenoid Open Circuit - Komatsu PC88MR-10 Shop Manual

40 Troubleshooting
Troubleshooting by failure code (Display of code)

Failure code [DXA8KA] Front Pump PC-EPC Solenoid Open Circuit

DXA8KA-400-A-Z0-A)
Action level Failure code
L03 DXA8KA
No current flows when pump controller drives PC-EPC solenoid, so pump controller
Detail of
determines that open circuit exists in PC-EPC solenoid circuit.
failure
None in particular (Since no current flows, solenoid is not energized.)
Action of
If cause of failure disappears, machine becomes normal by itself.
controller
Problem on
If pump load increases, engine speed decreases largely and engine may stall.
machine
When solenoid and wiring harness are normal, engine can be prevented from stalling by
setting pump secondary drive switch to ON position.
Related
Drive current of PC EPC solenoid can be checked by using monitoring function.
information
(Code: 01300)
Method of reproducing failure code: Turn starting switch to ON position.
No. Cause
Incorrect operation of
1 pump secondary drive
switch
Defective PC-EPC
solenoid
2
(Internal open circuit)
Defective pump
secondary drive
3
(Internal open circuit)
Open circuit, short
circuit, ground fault, hot
short circuit of wiring
4
harness, or defective
pump controller
Open or short circuit in
5
wiring harness
Open circuit in wiring
harness
6 (Wire breakage or
defective contact of
connector)
Pump controller is
7
defective.
40-352
Front Pump PC-EPC Solenoid Open Circuit
Failure
(Pump controller system)
Procedure, measuring location, criteria, and remarks
Set pump secondary drive switch at its normal position (lower side).
1. Turn starting switch to OFF position.
2. Disconnect connector V11, and connect T-adapter to male side.
Resistance Between V11 (male) (1) and (2)
1. Turn starting switch to OFF position.
2. Disconnect connector S25 and connect T-adapter to male side.
Between S25 (male) (3)
and (2)
Resistance
Between S25 (male) (6)
and (5)
1. Turn starting switch to OFF position.
2. Disconnect connector V11, and connect T-adapter to female side.
3. Turn starting switch to ON position.
a Shake the wiring harness by hand while measuring the voltage. If the
voltage drops to approximately 0 V during shaking, circuit is open around
this point.
Voltage Between V11 (male) (1) and (2)
a If no failure is found by check on cause 4, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connector CP02 and connect T-adapter to female side.
a Check that pump secondary drive switch is at normal position (lower side).
Between CP02 (female) (96) and each of (115),
Resistance
(117), and (120)
a If no failure is found by check on cause 4, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors CP02, S25 and V11, and connect T-adapters to
each female side.
Between CP02 (female) (96) and S25 (female) (3)
Between S25 (female) (2) and V11 (female) (1)
Resistance
Between S25 (female) (6) and each of CP02
(female) (115), (117), (120)
Between S25 (female) (5) and V11 (female) (2)
If no failure is found by above checks, pump controller is defective.
(Since this is an internal defect, troubleshooting cannot be performed.)
Switch position: Normal
Switch position:
Emergency
Switch position: Normal
Switch position:
Emergency
(PC88MR-
3 to 14 z
Max. 1 z
Min. 1 Mz
Max. 1 z
Min. 1 Mz
Min. 20 V
3 to 14 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
PC88MR-10