Yamaha YZ 2016 Series Owner's Service Manual page 339

TIP
Disconnect the fuel pump coupler when this diagnostic tool is used.
Fault code No.
Item
Fail-safe system
Diagnostic code No.
Actuation
Procedure
Probable cause of malfunc-
Item
tion and check
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).
2 Defective injector.
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).
4 Wire harness continuity.
5 Malfunction in ECU.
6 Delete the fault code.
39
Injector: open or short circuit detected.
Unable to start engine
Unable to drive vehicle
36
Actuates injector five times at one-second intervals.
The "WARNING" on the Yamaha diagnostic tool screen come on
each time the injector is actuated.
Check that injector is actuated five times by listening for the oper-
ating sound.
Maintenance job
Improperly connected 
Connect the coupler securely
or repair/replace the wire har-
ness.
Measure the fuel injector re-
sistance.
Replace if out of specifica-
tion.
Refer to "CHECKING THE
FUEL INJECTOR" on page 8-
68.
Improperly connected 
Connect the coupler securely
or repair/replace the wire har-
ness.
Open or short circuit  Re-
place the wire harness.
Between injector coupler and
ECU coupler.
red/black–red/black
red–red/blue
Replace the ECU.
—
8-37
FUEL INJECTION SYSTEM
Confirmation of service
completion
Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 2.
Operating sound  Go to
item 6.
Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 3.
Operating sound  Go to
item 6.
Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 4.
Operating sound  Go to
item 6.
Execute the diagnostic mode
(Code No. 36).
No operating sound  Go to
item 5.
Operating sound  Go to
item 6.
—
Start the engine and let it idle
for approximately 5 seconds.
Check that the fault code
number is not displayed.