Yamaha T135SE Service Manual page 326

EAS00797
2. The tail/brake light fails to come on.
1. Tail/brake light bulb and socket
9 Check the tail/brake light bulb and socket for
continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS".
9 Are the tail/brake light bulb and socket OK?
YES
2. Brake light switches
9 Check the brake light switches for continuity.
Refer to "CHECKING THE SWITCHES".
9 Is the brake light switch OK?
YES
SIGNALING SYSTEM
NO
Replace the tail/
brake light bulb,
socket or both.
NO
Replace the brake
light switch.
8-34
http://www.motorcycle.in.th
3. Voltage
9 Connect the pocket tester (DC 20 V) to the
tail/brake light coupler (wire harness side) as
shown.
→→
Positive tester probe
→→
Negative tester probe
9 Set the main switch to "ON".
9 Pull in the brake lever or push down on the
brake pedal.
9 Measure the voltage (DC 12 V) of green/yel-
1 on the tail/brake light
low lead terminal
coupler (wire harness side).
9 Is the voltage within specification?
YES
This circuit is OK.
ELEC
11
green/yellow
22
black
1
2
B L L B
Y G/Y
Ch Dg Dg Ch
NO
The wiring circuit
from the main
switch to the
tail/brake light cou-
pler is faulty and
must be repaired.