Yamaha YZ 2019 Series, Owner'S Service Manual

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FUEL INJECTION SYSTEM
8-42
Fault code No. Er-3
TIP
Before troubleshooting, disconnect the starter motor lead from the starter motor.
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 job
Confirmation of service com-
pletion
1 Connection of Yamaha diagnos-
tic tool coupler.
Check the locking condition of
the coupler.
Disconnect the coupler and
check the pins (bent or broken
terminals and locking condition
of the pins).
Improperly connected

Con-
nect the coupler securely or
repair/replace the wire harness.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is displayed

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 broken
terminals and locking condition
of the pins).
Improperly connected

Con-
nect the coupler securely or
repair/replace the wire harness.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is displayed

Go to item 3.
3 Wire harness continuity. Open or short circuit

Replace
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 displayed

Go to item 4.
4 Yamaha diagnostic tool mal-
function.
Replace the Yamaha diagnostic
tool.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is displayed

Go to item 5.
5 Malfunction in ECU. Replace the ECU.