Komatsu WA900-3E0 Shop Manual page 93

Troubleshooting by failure code
Failure code [DDDKKY] (Ladder raise operation switch hot short circuit)
No. Cause
6 Defective diode
Defective power ladder controller
a If monitoring results satisfy
7 conditions shown on the right,
this failure code does not ap-
pear and system is normal.
40-36
Procedure, measuring location, criteria and remarks
1. Turn starting switch to OFF position.
2. Disconnect PD03.
a Measure with multimeter in diode range.
Between PD03 (male) (1) (+) and PD03 (male) (2)
(-)
Between PD03 (male) (3) (+) and PD03 (male) (2)
(-)
Continuity
Between PD03 (male) (2) (+) and PD03 (male) (1)
(-)
Between PD01 (male) (2) (+) and PD01 (male) (3)
(-)
1. Turn starting switch to ON position and perform troubleshooting with moni-
toring function.
Code: 40989 "D-IN-0"
Code: 40989 "D-IN-0"
Displayed
value
Code: 40989 "D-IN-4"
Code: 40989 "D-IN-4"
Continuity
Continuity
No continu-
ity
No continu-
ity
"0" is displayed when
RAISE switch is OFF.
"1" is displayed when
RAISE switch is ON.
"0" is displayed when
parking brake is applied.
"1" is displayed when
parking brake is
released.
WA900-3E0