Komatsu WA250-6 Shop Manual

SEN03845-00
40-350 8 WA250, 250PZ-6
350 Troubleshooting by failure code (Display of code), Part 5
Failure code [DD1NL4] Fan automatic reverse switch signal: Abnormality
Failure code [DD1NL4] Fan automatic reverse switch signal: Abnormality
Action code Failure code
Trouble
Fan automatic reverse switch signal: Abnormality
(HST controller system)
E01 DD1NL4
Contents of
trouble
• Because of hot short in fan automatic reverse switch system, fan automatic reverse switch input and
fan manual reverse switch input were sensed simultaneously.
Action of
controller
• Turns automatic reverse switch function OFF.
Problem that
appears on
machine
• After error is detected, fan does not reverse.
• Automatic reverse switch LED lamp keeps lighting.
Related
information
• Input state from fan automatic reverse switch can be checked with monitoring function
(Code: HST – 93400 – FAN REVERSE SW) (Code: MONITOR PANEL – 40901 – D-IN-9).
• Method of reproducing failure code: Turn starting switch ON.
Possible causes
and standard
value in normal
state
Causes Standard value in normal state/Remarks on troubleshooting
1
Defective fan automatic
reverse switch (Internal short
circuit)
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
L69 (male)
Fan automatic reverse
switch
Resistance
Between (3), (4) – (5)
ON Max. 1 z
OFF Min. 1 Mz
2
Hot short in wiring harness
(Contact with 24V circuit)
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
(Carry out troubleshooting with automatic reverse switch OFF)
Wiring harness between L25 (female) (14) –
L69 (female) (3), (4) and ground
Voltage Max. 1 V
3 Defective machine monitor
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
L25 (male)
Fan automatic reverse
switch
Voltage
Between (14) and
ground
ON 20 – 30 V
OFF Max. 1 V

Komatsu WA250-6 Specifications

General

Brand	Komatsu
Model	WA250-6
Category	Compact Loader
Language	English