Checking The Lighting System - Yamaha T135SE Service Manual

EAS00788

CHECKING THE LIGHTING SYSTEM

1. The headlight and the high beam indicator
light fail to come on.
EAS00784
1. Dimmer switch
9Check the dimmer switch for continuity.
Refer to "CHECKING THE SWITCHES".
9Is the dimmer switch OK?
YES
2. Headlight bulb and socket
9Check the headlight bulb and socket for con-
tinuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS".
9Are the headlight bulb and socket OK?
YES
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Yamaha T135 Service Manual
NO
The dimmer switch
is faulty. Replace
the left handlebar
switch.
NO
Replace the head-
light bulb, socket or
both.
8-27
LIGHTING SYSTEM
3. Voltage
9Connect the pocket tester (AC 20 V) to the
headlight and high beam indicator light con-
nectors as shown.
åWhen the dimmer switch is set to "%".
∫When the dimmer switch is set to "&".
Headlight
Positive tester probe → →
Negative tester probe → → black 3 3
High beam indicator light
Positive tester probe → → yellow 4 4
Negative tester probe → → black 5 5
9Set the main switch to "ON".
9Start the engine.
9Set the dimmer switch to "%" or "&".
9Measure the voltage (AC 12 V) of green 1
(yellow 2) on the headlight connector (wire
harness side) and yellow 4 on the meter
assembly connector (wire harness side).
9Is the voltage within specification?
YES
This circuit is OK.
ELEC
green 1 1 or yellow 2 2
NO
Replace the rectifi-
er/regulator.