check engine light YAMAHA WR 250F 2017 User Guide

FUEL INJECTION SYSTEM
9-45
2 Installed condition of lean an-
gle sensor.Check the installed direction
and condition of the sensor.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 Defective lean angle sensor. Execute the diagnostic mode.
(Code No. 08)
Replace if defective.
Refer to “CHECKING THE
LEAN ANGLE SENSOR” on
page 9-75.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 Malfunction in ECU. Replace the ECU.
Fault code No. 33
ItemIgnition coil: open or short circuit detected in the primary lead
of the ignition coil.
Fail-safe systemUnable to start engine
Unable to drive vehicle
Diagnostic code No.30
ActuationActuates the ignition coil five times at one-second intervals.
The engine trouble warning light and the “WARNING” on the
Yamaha diagnostic tool screen come on each time the ignition coil
is actuated.
ProcedureCheck that a spark is generated five times.
• Connect an ignition checker.
ItemProbable cause of malfunc-
tion and checkMaintenance jobConfirmation of service
completion
1 Connection of ignition coil
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.Start the engine and let it idle
for approximately 5 seconds.
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.Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played  Service is finished.
Fault code number is dis-
played  Go to item 3. Fault code No. 30
Item Latch up detected.

FUEL INJECTION SYSTEM
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Disconnect the fuel pump coupler when this diagnostic tool is used.
Fault code No. 39
Item Injector: open or short circuit detected.
Fail-safe systemUnable to start engine
Unable to drive vehicle
Diagnostic code No.36
ActuationActuates injector five times at one-second intervals.
The engine trouble warning light and the “WARNING” on the
Yamaha diagnostic tool screen come on each time the injector is
actuated.
ProcedureCheck that injector is actuated five times by listening for the oper-
ating sound.
ItemProbable cause of malfunc-
tion and checkMaintenance jobConfirmation of service
completion
1 Connection of injector cou-
pler.
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.Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 2.
Operating sound  Go to
item 6.
2 Defective injector. Measure the fuel injector re-
sistance.
Replace if out of specifica-
tion.
Refer to “CHECKING THE
FUEL INJECTOR” on page 9-
81.Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 3.
Operating sound  Go to
item 6.
3 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.Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 4.
Operating sound  Go to
item 6.
4 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
Between injector coupler and
ECU coupler.
red/black–red/black
red–red/blueExecute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 5.
Operating sound  Go to
item 6.
5 Malfunction in ECU. Replace the ECU. —
6 Delete the fault code. — Start the engine and let it idle
for approximately 5 seconds.
Check that the fault code
number is not displayed.

FUEL INJECTION SYSTEM
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TIP
Before troubleshooting, disconnect the starter motor lead from the starter motor. 3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light greenPush 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
ItemSignals from the ECU cannot be received within the specified
period of time.
Fail-safe systemAble to start engine
Able to drive vehicle
Diagnostic code No.—
Diagnostic tool display—
Procedure—
ItemProbable cause of malfunc-
tion and checkMaintenance 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 greenPush the start switch.
Fault code number is not dis-
played  Service is finished.
Fault code number is dis-
played  Go to item 4. Fault code No. Waiting for connection
Item No communication signal is received from the ECU.

FUEL INJECTION SYSTEM
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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 systemAble to start engine
Able to drive vehicle
Diagnostic code No.—
Diagnostic tool display—
Procedure—
ItemProbable cause of malfunc-
tion and checkMaintenance 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 greenPush 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
ItemSignals from the ECU cannot be received within the specified
period of time.

FUEL INJECTION SYSTEM
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Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. Er-4
ItemRegistered data cannot be received from the Yamaha diagnos-
tic tool.
Fail-safe systemAble to start engine
Able to drive vehicle
Diagnostic code No.—
Diagnostic tool display—
Procedure—
ItemProbable cause of malfunc-
tion and checkMaintenance 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 greenPush 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.