Yamaha YZ450FA 2011, Owner'S Service Manual

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FUEL INJECTION SYSTEM
Fault code No. 46
Symptom Power supply to the ECU is not normal.
Fail-safe system Able to start (depending on circumstances)
Able to drive vehicle (depending on circumstances)
Diagnostic code No. —
FI diagnostic tool dis-
play
—
Checking method —
Item Item/components and probable cause Check or maintenance job Checking method
1 Check the connection and locking con-
dition of the ECU coupler.
Disconnect the coupler and check the
pins. (bent or broken terminals and
locking condition of the pins) Poor connection
→
Properly
connect, repair, or replace.
Start the engine, set
the switch on the FI di-
agnostic tool sub-wire
harness to "OFF"
while the engine is
idling, and let the en-
gine continue to idle
for 5 seconds or more.
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 displayed
→
Re-
fer to item 2.
2 Continuity of harness Open or short circuit
→
Re-
place.
Between Rectifier/regulator
and the ECU
(Red–Red/White)
Between Rectifier/regulator
and the condenser.
(Red–Red)
Start the engine, set
the switch on the FI di-
agnostic tool sub-wire
harness to "OFF"
while the engine is
idling, and let the en-
gine continue to idle
for 5 seconds or more.
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 displayed
→
Re-
fer to item 3.