Troubleshooting - Yamaha MBK MW125 2014 Service Manual

EAS30492

TROUBLESHOOTING

The ignition system fails to operate (no spark or intermittent spark).
TIP
• Before troubleshooting, remove the following part(s):
1. Fuse box cover
2. Center cover
3. Radiator cover
4. Front upper panel
5. Lower leg shield
1. Check the fuses.
(Main and signaling system)
Refer to "CHECKING THE FUS-
ES" on page 8-59.
OK ↓
2. Check the battery.
Refer to "CHECKING AND
CHARGING THE BATTERY" on
page 8-60.
OK ↓
3. Check the spark plugs.
Refer to "CHECKING THE SPARK
PLUG" on page 3-4.
OK ↓
4. Check the ignition spark gap.
Refer to "CHECKING THE IGNI-
TION SPARK GAP" on page 8-64.
NG ↓
5. Check the ignition coil.
Refer to "CHECKING THE IGNI-
TION COIL" on page 8-63.
OK ↓
6. Check the crankshaft position sen-
sor.
Refer to "CHECKING THE CRANK-
SHAFT POSITION SENSOR" on
page 8-64.
OK ↓
7. Check the main switch.
Refer to "CHECKING THE
SWITCHES" on page 8-55.
OK ↓
NG →
Replace the fuse(s).
NG →
• Clean the battery terminals.
• Recharge or replace the battery.
NG →
Re-gap or replace the spark plug(s).
OK →
Ignition system is OK.
NG →
Replace the ignition coil(s).
NG →
Replace the stator coil assembly.
NG →
Replace the main switch.
8-3
IGNITION SYSTEM