Yamaha YZ450FA Automobile User Manual


 
7-41
FUEL INJECTION SYSTEM
2 Check the connection and locking con-
dition of the wire harness 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.
Set the switch on the
FI diagnostic tool sub-
wire harness to "ON",
and then check the
fault code display.
Fault code number
is not displayed
Service is finished.
Fault code number
is displayed Re-
fer to item 3.
3 Continuity of harness Open or short circuit Re-
place.
Between FI diagnostic tool
coupler and ECU coupler.
(Light green–Light green)
Set the switch on the
FI diagnostic tool sub-
wire harness to "ON",
and then check the
fault code display.
Fault code number
is not displayed
Service is finished.
Fault code number
is displayed Re-
fer to item 4.
4 FI diagnostic tool malfunction Replace the FI diagnostic
tool.
Set the switch on the
FI diagnostic tool sub-
wire harness to "ON",
and then check the
fault code display.
Fault code number
is not displayed
Service is finished.
Fault code number
is displayed Re-
fer to item 5.
5 Malfunction in ECU. Replace the ECU.
Fault code No. waiting for connection
Symptom Communication signal is not received.
Fail-safe system Able to start (unable when ECU is malfunctioning)
Able to drive vehicle (unable when ECU is malfunctioning)
Diagnostic code No.
FI diagnostic tool dis-
play
Checking method
Item Item/components and probable cause Check or maintenance job Checking method