Yamaha CS50 Service Manual page 189

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
Replace the
tail/brake light bulb,
socket or both.
2. Brake light switches
• Check the brake light switches for conti-
nuity.
Refer to "CHECKING THE SWITCHES".
• Is the brake light switch OK?
YES
Replace the brake
light switch.
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
L
2
B
NO
NO
green/yellow
black
G/Y
1
SIGNALING SYSTEM
• Set the main switch to "ON".
• Pull in the brake levers.
• Measure the voltage (DC 12 V) of
green/yellow
pler (wire harness side).
• Is the voltage within specification?
YES
This circuit is OK.
EAS00799
3. The turn signal light, turn signal indicator
light or both fail to blink.
1. Turn signal indicator light bulb and socket
• Check the turn signal light bulb and socket
for continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS"
• Are the turn signal light bulb and socket
OK?
YES
2. Turn signal switch
• Check the turn signal switch for continuity.
Refer to "CHECKING THE SWITCHES".
• Is the turn signal switch OK?
YES
8-30
ELEC
on the tail/brake light cou-
NO
The wiring circuit
from the main
switch to the
tail/brake light cou-
pler is faulty and
must be repaired.
NO
Replace the turn
signal light bulb,
socket or both.
NO
Replace the left
handlebar switch.