Failure Code [Ddd7Kx] Travel Speed Control Dial Signal: Disconnection/Ground Fault - Komatsu WA250-6 Shop Manual

SEN03845-00
Failure code [DDD7KX] Travel speed control dial signal: Disconnection/
Ground fault
Action code Failure code
E01 DDD7KX
Contents of
• Travel speed control dial signal voltage lowered below 0.3 V.
trouble
Action of • Continue controls on assumption that travel speed control dial is set to minimum speed side.
controller
• Even if trouble disappears, system does not reset itself until starting switch is turned OFF.
Problem that
• Travel speed cannot be adjusted with travel speed control dial.
appears on
• If speed range selector switch is set in 1st, travel speed is set to about 4 km/h.
machine
Related
• If failure code [DAJ5KX] is also displayed, carry out troubleshooting for it first.
information
Defective travel speed con-
1
trol dial (Internal defect)
Disconnection in wiring har-
ness (Disconnection in wiring
2
or defective contact in con-
Possible causes
nector)
and standard
value in normal
state
Ground fault in wiring har-
3 ness (Contact with GND cir-
cuit)
4 Defective HST controller
22
40-350

Failure code [DDD7KX] Travel speed control dial signal: Disconnection/Ground fault

Travel speed control dial signal: Disconnection/Ground fault
Trouble
(HST controller system)
Causes
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
Between L54 (female) (A) – (C)
Between L54 (female) (B) – (C) (Max. speed
side of dial)
Between L54 (female) (B) – (C) (Min. speed
side of dial)
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between HST (female) (23) –
L54 (female) (B)
Wiring harness between HST (female) (22) –
L54 (female) (A)
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Between wiring harness HST (female) (23) –
L54 (female) and ground
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
350 Troubleshooting by failure code (Display of code), Part 5
Standard value in normal state/Remarks on troubleshooting
HST (female)
Between (32) – ground
HST (female)
Between (22) – ground
Between (23) – ground
4.7 – 5.3
Voltage
V
0.3 – 0.9
Voltage
V
4.1 – 4.7
Voltage
V
Resis-
Max. 1 z
tance
Resis-
Max. 1 z
tance
Resis- Min.
tance 1 Mz
Resistance
Max. 1 z
Voltage
4.7 – 5.3 V
0.3 – 4.7 V
WA250, 250PZ-6