Troubleshooting By Failure Code; Failure Code [D1Emka] (Disconnection Of Parking Brake Interlock Relay) - Komatsu WA900-3E0 Shop Manual

Troubleshooting by failure code

Failure code [D1EMKA] (Disconnection of parking brake interlock
Action level Failure code
E03 D1EMKA
Detail of failure Controller detects open circuit while driving parking brake interlock relay.
q
Action of con-
Stops driving solenoid and buzzer until its power supply is turned off.
q
troller
Ladder does not move when switch is operated.
q
Problem on
Parking brake can be released (parking brake interlock does not function) even if ladder is not
q
machine
stored in position.
Ladder can be moved to storage and boarding positions by using emergency release valve.
q
Output signal to parking brake interlock relay can be checked with monitoring function.
q
Code: 40990 "D-OUT-0" (ON: 1, OFF: 0)
Even when parking brake interlock relay has open circuit, ladder RAISE and LOWER operations
q
Related infor-
are possible if this failure code disappears and interlock relay is not activated. (When ladder is
mation
stored in position with starting switch at OFF position, controller does not drive interlock relay even
if parking brake releasing operation is performed.)
If interlock relay is activated when parking brake emergency release connector in fuse box is dis-
q
connected (emergency release state), this failure code appears.
No. Cause
Open circuit in wiring harness
1 (wire breakage or defective con-
tact of connector)
Defective parking brake interlock
2
relay
3 Defective power ladder controller
WA900-3E0

Failure code [D1EMKA] (Disconnection of parking brake interlock relay)

Failure Open circuit in parking brake interlock relay
Procedure, measuring location, criteria and remarks
1. Turn starting switch to OFF position.
2. Disconnect PC0 and PL12.
Between PC0 (female) (9) and PL12 (female) (1)
Resistance
Between PC0 (female) (40) and PLCU (female) (2)
1. Turn starting switch to OFF position.
2. Disconnect PL12.
Between PL12 (male) (1) and (2)
Resistance
Between ground and each of PL12 (male) (1) and
(2)
If no failure is found by check on causes 1 and 2, power ladder controller may
be defective. (Since this is an internal defect, troubleshooting cannot be per-
formed.)

Troubleshooting by failure code

relay)4 0 - 9
Max. 1 z
Max. 1 z
200 to 400 z
Min. 1 Mz
4 0 - 9
40-9