FUEL INJECTION SYSTEM
9-54
TIP
Before troubleshooting, disconnect the starter motor lead from the starter motor.4 Yamaha diagnostic tool mal-
function. Replace the Yamaha diag-
nostic tool. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 5.
5 Malfunction in ECU. Replace the ECU.
Fault code No. Er-3
Item Data from the ECU cannot be received correctly.
Fail-safe system Able to start engine
Able to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of Yamaha diag- nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected
Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected
Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 3.
3 Wire harness continuity. Open or short circuit Re-
place the wire harness.
light green–light green Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 4.
4 Yamaha diagnostic tool mal- function. Replace the Yamaha diag-
nostic tool. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 5.
5 Malfunction in ECU. Replace the ECU. Fault code No. Er-2
Item Signals from the ECU cannot be received within the specified
period of time.
FUEL INJECTION SYSTEM
9-55
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. Er-4
Item Registered data cannot be received from the Yamaha diagnos-
tic tool.
Fail-safe system Able to start engine
Able to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of Yamaha diag- nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected
Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected
Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 3.
3 Wire harness continuity. Open or short circuit Re-
place the wire harness.
light green–light green Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 4.
4 Yamaha diagnostic tool mal- function. Replace the Yamaha diag-
nostic tool. Push the start switch.
Fault code number is not dis-
played
Service is finished.
Fault code number is dis-
played Go to item 5.
5 Malfunction in ECU. Replace the ECU.
