Troubleshooting - Yamaha YFM250RX 2008 Service Manual

EBS01045

TROUBLESHOOTING

The ignition system fails to operate (no
spark or intermittent spark).
Check:
1. fuse
2. battery
3. spark plug
4. ignition spark gap
5. ignition coil resistance
6. main switch
7. engine stop switch
8. pickup coil resistance
9. wiring connections (of the entire ignition
system)
NOTE: NOTE:
• Before troubleshooting, remove the following
part(s):
1. seat
2. front panel
3. front fender
4. rear fender
5. side cover
• Troubleshoot with the following special
tool(s).
Ignition checker
90890-06754
Opama pet-4000 spark checker
YM-34487
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
EBS01043
1. Fuse
• Check the fuse for continuity.
Refer to "CHECKING THE SWITCHES".
• Is the fuse OK?
YES
NO
Replace the fuse.
7-9
IGNITION SYSTEM
EBS01044
2. Battery
• Check the condition of the battery.
Refer to "CHECKING AND CHARGING
THE BATTERY" in chapter 3.
Minimum open-circuit voltage
12.8 V or more at 20°C (68°F)
• Is the battery OK?
YES
EBS01032
3. Spark plug
• Check the condition of the spark plug.
• Check the spark plug type.
• Measure the spark plug gap.
Refer to "CHECKING THE SPARK PLUG"
in chapter 3.
Standard spark plug
DR7EA (NGK)
Spark plug gap
0.6 ~ 0.7 mm (0.024 ~ 0.028 in)
• Is the spark plug in good condition, is it of
the correct type, and is its gap within speci-
fication?
YES
ELEC
NO
• Clean the battery
terminals.
• Recharge or replace
the battery.
NO
Re-gap or replace
the spark plug.