E-15 Horn Does Not Sound Or It Keeps Sounding - Komatsu WA250-6 Shop Manual

SEN03848-00

E-15 Horn does not sound or it keeps sounding

Contents of
Horn does not sound or it keeps sounding.
trouble
Related
information
Defective fuse No.9 of fuse
1
box (FS2)
Defective horn relay (L116)
2
(Internal trouble)
Defective L13 horn switch
3
(Internal trouble)
Possible
causes and
standard value
in normal state
Defective horn
4
(Internal trouble)
Disconnection in wiring har-
ness
5
(Disconnection or defective
contact in connector)
66
40-400
Causes
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 horn relay (L116) is replaced with a relay of the same type, if
the condition becomes normal, the horn relay is defective.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Between (1) and
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting. (Disconnect connector and mea-
sure on female side)
Between F01 (1) and
Between F02 (1) and
a If horn does not sound normally under above condition, it is
defective.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between fuse No. 9 of fuse
box (FS2) – L116 (female) (1), (3)
Wiring harness between L116 (female) (2) –
L13 (female) (1)
Wiring harness between L116 (female) (5) –
F01 (female) (1), – F02 (female) (1)
Wiring harness between F01 (female) (2) –
F02 (female) (2) – ground
Wiring harness between steering wheel horn
switch – ground
400 Troubleshooting of electrical system (E-mode)
E-15 Horn does not sound or it keeps sounding
—
Standard value in normal state/Remarks on troubleshooting
L116 (male)
Between (1) and (2)
L13 (male) Horn switch
ground
F01, F02 Horn switch
(2)
(2)
Resistance
200 – 400 z
Resistance
ON Max. 1 z
OFF Min. 1 Mz
Voltage
ON Max. 1 V
OFF 20 – 30 V
ON Max. 1 V
OFF 20 – 30 V
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