Troubleshooting - Yamaha WR250F Owner's Service Manual

TROUBLESHOOTING

EAS2GB2361
The ignition system fails to operate (no spark or intermittent spark).
TIP
Before troubleshooting, remove the following part (s):
1. Seat
2. Side cover (left/right)
3. Air scoop (left/right)
4. Fuel tank
5. Fuel tank
1. Check the fuse.
Refer to "CHECKING THE FUSES"
on page 9-68.
OK 
2. Check the battery.
Refer to "CHECKING AND
CHARGING THE BATTERY" on
page 9-69.
OK 
3. Check the spark plug.
Refer to "CHECKING THE FUSES"
on page 9-68.
OK 
4. Check the ignition spark gap.
Refer to "CHECKING THE IGNI-
TION SPARK GAP" on page 9-73.
NG 
5. Check the ignition coil.
Refer to "CHECKING THE IGNI-
TION COIL" on page 9-74.
OK 
6. Check the crankshaft position sen-
sor.
Refer to "CHECKING THE CRANK-
SHAFT POSITION SENSOR" on
page 9-74.
OK 
7. Check the engine stop switch.
Refer to "CHECKING THE
SWITCHES" on page 9-64.
OK 
NG 
Replace the fuse(s).
NG 
• Clean the battery terminals.
• Recharge or replace the battery.
NG 
Re-gap or replace the spark plug.
OK 
The ignition system is normal.
NG 
Replace the ignition coil.
NG 
Replace the stator assembly.
NG 
Replace the engine stop switch.
9-4
IGNITION SYSTEM