Checking The Signaling System - Yamaha TW125 1999 Service Manual

EAS00796

CHECKING THE SIGNALING SYSTEM

1. The horn fails to sound.
1. Horn switch
S Check the horn switch for continuity.
Refer to "CHECKING THE SWITCHES".
S Is the horn switch OK?
YES
2. Voltage
S Connect the pocket tester (DC 20 V) to the
horn connector at the horn terminal as
shown.
Tester positive probe ! brown
Tester negative probe ! ground
S Set the main switch to "ON".
S Push the horn switch.
S Measure the voltage (12 V) of brown at the
horn terminal.
S Is the voltage within specification?
YES
NO
Replace the left han-
dlebar switch.
1
NO
The wiring circuit
from the main switch
to the horn connector
is faulty and must be
repaired.
SIGNAL SYSTEM
3. Horn
S Disconnect the pink connector at the horn
terminal.
S Connect a jumper lead
and ground the jumper lead.
S Set the main switch to "ON".
S Push the horn switch.
S Does the horn sound?
NO
4. Voltage
S Connect the pocket tester (DC 20 V) to the
horn connector at the black terminal as
shown.
Tester positive probe ! pink
Tester negative probe ! ground
S Set the main switch to "ON".
S Measure the voltage (12 V) of pink
horn terminal.
S Is the voltage within specification?
YES
Repair or replace the
horn.
7-30
ELEC
1 to the horn terminal
YES
The horn is OK.
1
1 at the
NO
Replace the horn.