Failure Code [Dwnlka] (Ladder Cushion Valve Output Open Circuit) - Komatsu WA900-3E0 Shop Manual

Troubleshooting by failure code

Failure code [DWNLKA] (Ladder cushion valve output open circuit)

Failure code [DWNLKA] (Ladder cushion valve output open circuit)

Action level Failure code
E01 DWNLKA
Detail of failure Controller detects open circuit while driving ladder cushion valve solenoid.
q
Action of con-
(None in particular)
q
troller
Problem on Ladder does not slow down before storage position.
q
machine Ladder does not slow down before boarding position.
q
Ladder can be raised and lowered although it does not slow down.
q
Related infor-
Output signal to ladder cushion valve can be checked with monitoring function.
q
mation
Code: 40991 "D-OUT-14" (ON: 1, OFF: 0)
No. Cause
Open circuit in wiring harness
1 (wire breakage or defective con-
tact of connector)
2 Defective cushion valve
3 Defective power ladder controller
40-50
Failure Open circuit in ladder cushion valve
Procedure, measuring location, criteria and remarks
1. Turn starting switch to OFF position.
2. Disconnect PC0 and PLCU.
Between PC0 (female) (29) and PLCU (female) (1)
Resistance
Between PC0 (female) (40) and PLCU (female) (2)
1. Turn starting switch to OFF position.
2. Disconnect PLCU.
Between PLCU (male) (1) and (2)
Resistance
Between PLCU (male) (1) and ground
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.)
4 0 - 5 0
Max. 1 z
Max. 1 z
21 to 32 z
Min. 1 Mz
WA900-3E0