Yamaha CS50 Service Manual page 184

• Set the main switch to "ON".
• Start the engine.
• Measure the voltage (DC 12 V) of blue
the meter light coupler (wire harness side).
• Is the voltage within specification?
YES
This circuit is OK.
EAS00790
3. 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. 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
G/Y
2
B
on
NO
The wiring circuit
from the main
switch to the meter
light coupler is
faulty and must be
repaired.
NO
blue
black
1
LIGHTING SYSTEM
• Set the main switch to "ON".
• Start the engine.
• Measure the voltage (DC 12 V) of blue
the tail/brake light coupler (tail/brake light
side).
• Is the voltage within specification?
YES
This circuit is OK.
EAS00791
4. The position light fails to come on.
1. Position light bulb and socket
• Check the position light bulb and socket for
continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS"
• Are the position light bulb and socket OK?
YES
2. Voltage
• Connect the pocket tester (DC 20 V) to the
position light coupler (wire harness side) as
shown.
Positive tester probe
Negative tester probe
8-25
ELEC
NO
Wiring circuit from
the main switch to
the tail/brake light
coupler is faulty and
must be repaired.
NO
Replace the posi-
tion light bulb,
socket or both.
blue
black
1
L L
B B
2
on