Yamaha CS50 - Troubleshooting

ELEC
LIGHTING SYSTEM
8-23
EAS00782
TROUBLESHOOTING
Check:
1. lighting coil resistance
2. dimmer switch
3. wiring connections
(of the entire charging system)
NOTE:
• Before troubleshooting, remove the follo-
wing part(s):
1. Front upper cowling
2. Footrest board
3. Handlebar cover (upper)
• Troubleshoot with the following special
tool(s).
1. Lighting coil resistance
• Disconnect the DC-CDI magneto coupler.
• Connect the pocket tester (Ωx1) to the
lighting coil as shown.
Positive tester probe

Yellow/red 
Negative tester probe

black 
• Measure the lighting coil resistance.
Lighting coil resistance:
0.116 ~0.264 Ω at 20°C
• Is the lighting coil OK?
EAS00784
2. Dimmer switch
• Check the dimmer switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the dimmer switch OK?
EAS00787
3. Wiring
• Check the entire lighting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
• Is the lighting system’s wiring properly con-
nected and without defects?
Pocket tester
90890-03112
Any of the following fail to light: head-
light, high beam indicator light, taillight,
position light, and meter light.
Replace the lighting
coil assembly
B
W
W
L
/
Y
R
/
2
1
The dimmer switch
is faulty. Replace
the left handlebar
switch.
Properly connect or
repair the lighting
system’s wiring.
Check the condition
of each of the
lighting system’s
circuits. Refer to
“CHECKING THE
LIGHTING
SYSTEM”.
YES
NO
YES
NO
YES
NO