Komatsu PC88MR-10 Shop Manual page 848

40 Troubleshooting
Troubleshooting by failure code (Display of code)
Failure code [DXE7KY] Attachment Flow Regulating EPC 2 Solenoid Hot
Short Circuit
(PC88MR-DXE7KY-400-A-Z0-A)
Action level Failure code
DXE7KY
Abnormal current flows when pump controller drives attachment flow rate (service current)
EPC2 solenoid, so pump controller determines that short circuit exists in attachment flow
Details of
rate adjustment (service current) EPC2 solenoid circuit.
failure
a Attachment flow rate adjustment EPC2 is ATT flow rate adjustment EPC2.
Stops driving attachment flow rate adjustment EPC2 solenoid.
Also sets output command to attachment flow rate adjustment EPC5 solenoid to 0 mA.
Action of
Even if cause of failure disappears, machine does not become normal until starting switch
controller
is turned to OFF position.
Problem on
Attachment does not move.
machine
Drive current of attachment flow rate adjustment EPC2 solenoid can be checked with
monitoring function.
Related
(Code: 01702)
information
Method of reproducing failure code: Turn starting switch ON and set machine in
attachment mode (ATT).
No. Cause
Defective attachment
flow rate adjustment
EPC2
1
(Internal short circuit or
ground fault)
Hot short circuit in
2
wiring harness
Pump controller is
3
defective.
40-360
Attachment Flow Regulating EPC 2 Solenoid Hot Short Circuit
Failure
(Pump controller system)
Procedure, measuring location, criteria, and remarks
1. Turn starting switch to OFF position.
2. Disconnect connector V92, and connect T-adapter to male side.
Between V92 (male) (1) and (2)
Resistance
Between V92 (male) (1) and ground
1. Turn starting switch to OFF position.
2. Disconnect connector V92, and connect T-adapter to female side of V92.
3. Turn starting switch to ON position.
Voltage Between V92 (female) (1) and ground
If no failure is found by above checks, pump controller is defective.
(Since this is an internal defect, troubleshooting cannot be performed.)
7 to 14 z
Min 1 Mz
Max 4.5 V
PC88MR-10