2016 YAMAHA YZ450F display

FUEL INJECTION SYSTEM
8-28
Fault code 50
Symptom ECU: faulty ECU memory
Fail-safe systemUnable to start engine
Unable to drive vehicle
Diagnostic code No.—
Diagnostic tool display—
Procedure—
Or-
derProbable cause of malfunc-
tion and checkMaintenance job Reinstatement method
1 Faulty ECU Replace the ECU. Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Check that the fault code
number is not displayed.
Fault code Waiting for connection
Symptom No communication signal is received from the ECU.
Fail-safe systemAble to start engine (Unable when ECU is malfunctioning)
Able to drive vehicle (Unable when ECU is malfunctioning)
Diagnostic code No.—
Diagnostic tool display—
Procedure—
Or-
derProbable cause of malfunc-
tion and checkMaintenance job Reinstatement method
1 Connection of Yamaha diag-
nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
2 Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light greenTurn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.

FUEL INJECTION SYSTEM
8-29
4 Yamaha diagnostic tool mal-
functionReplace the Yamaha diag-
nostic tool.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
5 Faulty ECU Replace the ECU.
Fault code Er-2
SymptomSignals 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—
Or-
derProbable cause of malfunc-
tion and checkMaintenance job Reinstatement method
1 Connection of Yamaha diag-
nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
2 Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light greenTurn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
4 Yamaha diagnostic tool mal-
functionReplace the Yamaha diag-
nostic tool.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
5 Faulty ECU Replace the ECU. Fault code Waiting for connection
Symptom No communication signal is received from the ECU.

FUEL INJECTION SYSTEM
8-30
Fault code Er-3
Symptom 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—
Or-
derProbable cause of malfunc-
tion and checkMaintenance job Reinstatement method
1 Connection of Yamaha diag-
nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
2 Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light greenTurn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
4 Yamaha diagnostic tool mal-
functionReplace the Yamaha diag-
nostic tool.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
5 Faulty ECU Replace the ECU.

FUEL INJECTION SYSTEM
8-31
Fault code Er-4
SymptomRegistered 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—
Or-
derProbable cause of malfunc-
tion and checkMaintenance job Reinstatement method
1 Connection of Yamaha diag-
nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
2 Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).Improperly connected 
Connect the coupler secure-
ly, or repair/replace the wire
harness.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light greenTurn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
4 Yamaha diagnostic tool mal-
functionReplace the Yamaha diag-
nostic tool.Turn “ON” the switch on the
FI diagnostic tool sub-lead.
Fault code No. is not dis-
played  Repair is finished.
Fault code No. is displayed 
Go to next order.
5 Faulty ECU Replace the ECU.

LIST OF SELF-DIAGNOSTIC AND FAIL-SAFE ACTIONS
9-5
SENSOR OPERATION TABLE
Diag-
nostic
code
No.ITEM Display Procedure
01 Throttle angle
• Fully closed position
• Fully opened positionDisplays the throttle angle.
• 11–14
• 109–116• Check with throttle fully
closed.
• Check with throttle fully
opened.
03 Pressure of suction pipe Displays the intake air pres-
sure.The atmospheric pressure
is displayed on the Yamaha
diagnostic tool.
05 Intake air temperature Displays the intake air tem-
perature.Compare the actually mea-
sured intake air tempera-
ture with the Yamaha
diagnostic tool display val-
ue.
06 Coolant temperature Displays the coolant temper-
ature.Compare the actually mea-
sured coolant temperature
with the Yamaha diagnostic
tool display value.
08 Lean angle sensor
• Upright
•OverturnDisplays the output voltage.
• 1.0 (V)
• 4.0 (V)Remove the ECU, and in-
cline it 45 ° or more.
09 Monitor voltage Displays the voltage of the
external battery connected to
the Yamaha diagnostic tool.
• Approximately 12.0 (V)—
21 Neutral switch
• Gear in neutral
• Gear not in neutral•ON
•OFFOperate the shift pedal.
25 Gear position switch
• Gear in 1st or 2nd
• Gear not in 1st or 2nd•ON
•OFFOperate the shift pedal.
60 EEPROM fault code No.
display
• No fault
• CO adjustment valve
• Power Tuner injection cor-
rection setting 0–8, or
Power Tuner ignition tim-
ing correction setting 0–8•00
•01
•07—
61 Malfunction history ( )
code No. display *1
• There is no history.
• There is some history.•00
• Other: Displays the fault
code of ( ).—

LIST OF SELF-DIAGNOSTIC AND FAIL-SAFE ACTIONS
9-6
*1: Symbols used in the explanations of the malfunction history
: Normal
: There is currently a malfunction or abnormal condition.
: A malfunction or abnormal condition occurred previously, but the affected system or component
is currently operating normally.
ACTUATOR OPERATION TABLE62 Malfunction history ( )
code No. erasure *1
• There is no history.
• There is some history.•00
• Other: Displays the total
number of ( ) and ( ).Replace all ( ) with ( )
by the operation start pro-
cessing.
64 Setting history display
• There is no history.
• There is some history.
• History is unknown (Histo-
ry data is damaged).Displays the presence or ab-
sence of the setting history by
Power Tuner.
•00
•01
•02—
65 Setting map erasure
• There is no setting.
• There is some setting.Displays the presence or ab-
sence of the setting history by
Power Tuner.
•00
•01Erase all setting maps by
the operation start process-
ing.
70 Program version number Displays a program version
No.—
Diag-
nostic
code
No.ITEM Actuation Procedure
30 Ignition coil Actuates the ignition coil five
times at one-second inter-
vals.
“WARNING” on the Yamaha
diagnostic tool blinks five
times when the ignition coil is
actuated.Check that a spark is gener-
ated five times.
• Connect an ignition
checker.
36 Injector Actuates the injector five
times at one-second inter-
vals.
“WARNING” on the Yamaha
diagnostic tool blinks five
times when the injector is ac-
tuated.TIP: Before performing
this operation, be sure to
disconnect the fuel pump
coupler.
Check that injector is actu-
ated five times by listening
for the operating sound. Diag-
nostic
code
No.ITEM Display Procedure