2010 YAMAHA WR 250F light

7-18
LIGHTING SYSTEM
LIGHTING SYSTEM
INSPECTION STEPS
Refer to the following flow chart when inspecting the lighting system for possible problems.
• Remove the following parts before inspection.
1. Seat
2. Fuel tank
3. Left side cover
• Use the following special tools in this inspection.
Check the bulb and bulb socket.No good→Replace the bulb and/or bulb socket.
OK ↓
Check the taillight (LEDs). No good→Replace the taillight assembly.
OK ↓
Check the AC magneto. (Lighting coil) No good→Replace.
OK ↓
Check the entire lighting system proper for con-
nections. Improperly
connected →Repair or replace.
OK ↓
Check the rectifier/regulator. (Out-put voltage) No good →Replace.
Pocket tester:
YU-3112-C/90890-03112

7-19
LIGHTING SYSTEM
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.
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 →Replace. 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 voltageOut of specification →Replace
rectifier/regulator.
Battery (+) terminal
→Blue lead
"2"
Battery (-) terminal →Black lead
"3"
Tester (+) lead →Yellow lead "1"
Tester (-) lead →Ground "2"
Lighting
coil resis-
tance Tester se-
lector posi-
tion
0.224–0.336 Ω at 20 °C (68 °F) Ω × 1
Tester (+) lead
→Yellow lead "1"
Tester (-) lead →Black lead "2"
Out-put voltage Tester se-
lector posi- tion
12.5–13.5 V at 5,000 r/ min ACV-20

7-20
SIGNALING SYSTEM
SIGNALING SYSTEM
INSPECTION STEPS
If the speedometer will not operate, use the following inspection steps.
*1 marked: Refer to "CHECKING AND CHARGIN G THE BATTERY" section in the CHAPTER 3.
• Remove the following parts before inspection.
1. Headlight
• Use the following special tools in this inspection.
*1 Check battery. No good→Recharge or replace.
OK ↓
Check each coupler and wire connection. No good →Repair or replace.
OK ↓
Check multi-function display. (Input voltage) No good →Replace wire harness.
OK ↓
Check multi-function displa y. (Output voltage) No good →Replace multi-function display.
OK ↓
Check speed sensor. No good→Replace.
Pocket tester:
YU-3112-C/90890-03112