Yamaha WR250F Owner's Service Manual page 217

CHECKING THE TAILLIGHT
(LEDs)
1. Disconnect the taillight coupler.
2. Connect two jumper leads "1"
from the battery terminals to the
respective coupler terminal as
shown.
→
Battery (+) terminal
"2"
→
Battery (-) terminal Black lead
"3"
3. Check:
• LED (for proper operation)
→
Does not light Replace the tail-
light assembly.
• A wire that is used as a jumper
lead must have at least the same
capacity of the battery lead, oth-
erwise the jumper lead may burn.
• This check is likely to produce
sparks, therefore, make sure no
flammable gas or fluid is in the
vicinity.
CHECKING THE AC MAGNETO
1. Inspect:
• Lighting coil resistance
→
Out of specification
→
Tester (+) lead Yellow lead "1"
→
Tester (-) lead Ground "2"
Lighting Tester se-
coil resis- lector posi-
tance
0.224–0.336
Ω
at 20 °C
(68 °F)
CHECKING THE RECTIFIER/
REGULATOR
1. Connect the battery leads.
2. Start the engine.
3. Turn on the headlight and taillight
by turning on the light switch.
4. Inspect:
• Out-put voltage
Out of specification
rectifier/regulator.
Tester (+) lead
Tester (-) lead
Blue lead
Replace.
tion
Ω
× 1
→
Replace
→
Yellow lead "1"
→
Black lead "2"
Tester se-
Out-put
lector posi-
voltage
tion
12.5–13.5 V
at 5,000 r/ ACV-20
min
7-19
LIGHTING SYSTEM