Yamaha WR450FN 2022 Owner's Service Manual page 303

9. Check the stator coil assembly.
Refer to "CHECKING THE STA-
TOR COIL" on page 8-67.
OK
10.Check the ignition system wire har-
ness.
Refer to "CIRCUIT DIAGRAM" on
page 8-1.
OK
Replace the ECU.
Replace the stator coil assembly.
NG
Repair or replace the wire harness.
NG
8-4
IGNITION SYSTEM