Troubleshooting - Yamaha SR400 2014 Service Manual

EAS27131

TROUBLESHOOTING

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)
3. Fuel tank
4. Crankcase cover (left)
5. Drive sprocket cover
1. Check the fuses.
(Main and ignition)
Refer to "CHECKING THE FUSES"
on page 7-59.
OK
2. Check the battery.
Refer to "CHECKING AND
CHARGING THE BATTERY" on
page 7-60.
OK
3. Check the spark plug.
Refer to "CHECKING THE SPARK
PLUG" on page 3-5.
OK
4. Check the ignition spark gap.
Refer to "CHECKING THE IGNI-
TION SPARK GAP" on page 7-66.
NG
5. Check the spark plug cap.
Refer to "CHECKING THE SPARK
PLUG CAP" on page 7-65.
OK
6. Check the ignition coil.
Refer to "CHECKING THE IGNI-
TION COIL" on page 7-65.
OK
7. Check the crankshaft position sen-
sor.
Refer to "CHECKING THE CRANK-
SHAFT POSITION SENSOR" on
page 7-67.
OK
8. Check the main switch.
Refer to "CHECKING THE
SWITCHES" on page 7-55.
OK
Replace the fuse(s).
NG
• Clean the battery terminals.
• Recharge or replace the battery.
NG
Re-gap or replace the spark plug.
NG
Ignition system is OK.
OK
Replace the spark plug cap.
NG
Replace the ignition coil
NG
Replace the stator coil assembly.
NG
Replace the main switch.
NG
7-5
IGNITION SYSTEM