E-10 Working Lamp Does Not Light Up Or Go Off - Komatsu WA250-6 Shop Manual

SEN03848-00

E-10 Working lamp does not light up or go off

Contents of
(1) Front working lamp does not light up or go off.
trouble
• The switch, lamp, or wiring harness of the front working lamp system is defective
Related
• When the rear working lamp is normal
information
• If the clearance lamp does not light up or go off either, carry out troubleshooting for the clearance
lamp first.
1 Broken bulb
Defective fuse No. 12 of fuse
2
box (FS2)
Defective front working lamp
3
relay (L122) (Internal trouble)
Possible
causes and
standard value
Defective front working lamp
4
in normal state
switch (Internal trouble)
Disconnection in wiring har-
ness
5
(Disconnection or defective
contact in connector)
46
40-400
Causes
If a specific working lamp does not light up, its bulb may be broken
or may have a defective contact. Check the bulb directly.
If the fuse is burn, the circuit probably has a grounding fault, etc.
(See cause 6.)
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.
When front working lamp relay (L122) is replaced with a relay of the
same type, if the condition becomes normal, the front working lamp
relay is defective.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Between (5) and (6)
Between (5), (6) and
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between L07 (female) (5) –
L122 (female) (1)
Wiring harness between L122 (female) (2) –
ground
Wiring harness between fuse No. 12 of fuse
box (FS2) – L07 (female) (6), L122 (female) (3)
Wiring harness between L122 (female) (5) –
C04 (female) (1), – C05 (female) (1)
Wiring harness between C04 (female) (2),
C05 (female) (2) – ground
400 Troubleshooting of electrical system (E-mode)
E-10 Working lamp does not light up or go off
Standard value in normal state/Remarks on troubleshooting
L122 (male)
Between (1) and (2)
Front working lamp
L07 (male)
ground
Resistance
200 – 400 z
Resistance
switch
Max. 1 z
ON
OFF Min. 1 Mz
Constant Min. 1 Mz
Resis-
tance
Resis-
tance
Resis-
tance
Resis-
tance
Resis-
tance
WA250, 250PZ-6
1
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z
Max. 1 z