Checking The Signaling System - Yamaha T135SE Service Manual

EAS00796

CHECKING THE SIGNALING SYSTEM

1. The horn fails to sound.
1. Horn switch
9Check the horn switch for continuity.
Refer to "CHECKING THE SWITCHES".
9Is the horn switch OK?
YES
2. Voltage
9Connect the pocket tester (DC 20 V) to the
horn connector at the horn terminal as
shown.
Positive tester probe → → brown 1 1
Negative tester probe → → ground
1
9Set the main switch to "ON".
9Measure the voltage (DC 12 V) of brown
lead terminal at the horn terminal.
9Is the voltage within specification?
YES
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Yamaha T135 Service Manual
NO
Replace the left han-
dlebar switch.
Br P
NO
The wiring circuit
from the main switch
to the horn connec-
tor is faulty and must
be repaired.
SIGNALING SYSTEM
3. Horn
9Disconnect the pink connector at the horn
terminal.
9Connect a jumper lead 1 to the horn termi-
nal and ground the jumper lead.
9Set the main switch to "ON".
9Does the horn sound?
Br
NO
4. Voltage
9Connect the pocket tester (DC 20 V) to the
horn connector at the pink terminal as
shown.
Positive tester probe → → pink 1 1
Negative tester probe → → ground
9Set the main switch to "ON".
9Measure the voltage (DC 12 V) of pink lead
terminal 1 at the horn terminal.
9Is the voltage within specification?
YES
Repair or replace
the horn.
8-33
ELEC
1
YES
The horn is OK.
Br P
1
NO
Replace the horn.