Yamaha XF50W Service Manual page 319

EAS00798
2. The tail/brake light fails to come on.
1. Tail/brake light bulb and socket
• Check the tail/brake light bulb and socket for
continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS"
• Are the tail/brake light bulb and socket OK?
YES
V
2. Brake light switches
• Check the brake light switches for continu-
ity.
Refer to "CHECKING THE SWITCHES".
• Is the brake light switch OK?
YES
V
NO
I
Replace the tail/brake
light bulb, socket or both.
NO
Replace the brake light
switch(es).
SIGNALING SYSTEM
3. Voltage
• Connect the pocket tester (DC 20 V) to the
tail/brake light coupler (wire harness side)
as shown.
Positive tester probe
Negative tester probe
• Set the main switch to "ON".
• Pull in the brake levers.
• Measure the voltage (DC 12 V) of green/
yellow © on the tail/brake light coupler (wire
harness side).
• Is the voltage within specification?
YES
V
This circuit is OK.
8-37
ELEC
green/ yellow 1
black 2
J®
G/Y
E
L
B
®
NO
4
The wiring circuit from
the main switch to the
tail/brake light coupler is
faulty and must be re-
paired.
Refer to "CIRCUIT DIA-
GRAM".
+i