Yamaha YZ450F Owner's Service Manual page 212

Fault code No.
Symptom
Fail-safe system
Diagnostic code No.
FI diagnostic tool display
Checking method
Item Item/components and probable cause
1 Check the connection and locking condition of
the ignition coil coupler.
Disconnect the coupler and check the pins.
(bent or broken terminals and locking condition
of the pins)
2 Check the connection and locking condition of
the wire harness ECU coupler.
Disconnect the coupler and check the pins.
(bent or broken terminals and locking condition
of the pins)
3 Continuity of harness
33
Ignition system circuit signal is not received properly.
Unable to start
Unable to drive
D30
Actuates the ignition coil for five times every second.
The "WARNING" LED on the FI diagnostic tool comes on each time the ignition coil is ac-
tuated.
Check the spark five times.
• Connect an ignition checker.
FUEL INJECTION SYSTEM
Check or maintenance job
Poor connection → Properly con-
nect, repair, or replace.
Poor connection → Properly con-
nect, repair, or replace.
Open or short circuit → Replace.
Between Ignition coil coupler and
ECU coupler.
(Orange–Orange)
7-26
Checking method
Start the engine and let it
idle for approximately 5
seconds.
After completing the above
operation, check whether a
fault code number is dis-
played.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 2.
Start the engine and let it
idle for approximately 5
seconds.
After completing the above
operation, check whether a
fault code number is dis-
played.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 3.
Start the engine and let it
idle for approximately 5
seconds.
After completing the above
operation, check whether a
fault code number is dis-
played.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 4.