Yamaha 2016 Grizzly yf700gg, Service Manual, Page: 402 / 474

FUEL INJECTION SYSTEM
9-47
A-4 ISC valve is not moving correct-
ly. Replace the throttle body as-
sembly. Start the engine and let it idle
for approximately 10 seconds.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item A-5.
A-5 Malfunction in ECU. Replace the ECU.
Fault code No. 37
Item
A
Component other than ISC (Idle Speed Control) unit is defective
(ISC operating sound is heard).
B
Defective ISC (Idle Speed Control) unit (ISC operating sound is
not heard).
Fail-safe system
Able to start engine
Able to drive vehicle
Diagnostic code No. 54
Actuation
Fully closes the ISC valve, and then opens the valve.
This operation takes approximately 3 seconds.
The “CHECK” indicator and “
” on the Yamaha diagnostic tool screen
come on during the operation.
Procedure The operating sound can be heard when ISC valve operates.
Item
Probable cause of malfunc-
tion and check
Maintenance job
Confirmation of service com-
pletion
B-1 Locate the malfunction. Execute the diagnostic mode.
(Code No. 54)
Fully closes the ISC (Idle Speed
Control) valve, and then fully
opens the valve. ISC operating sound is heard
→
Go to item A-2 for the compo-
nent other than ISC (Idle Speed
Control) unit is defective.
ISC operating sound is not
heard
→
Go to item B-2.
B-2 Connection of ISC (Idle Speed
Control) unit 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 re-
place the wire harness.
Execute the diagnostic mode.
(Code No. 54)
ISC operating sound is heard
→
Go to item B-8.
ISC operating sound is not
heard
→
Go to item B-3.
B-3 Connection of 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 re-
place the wire harness.
Execute the diagnostic mode.
(Code No. 54)
ISC operating sound is heard
→
Go to item B-8.
ISC operating sound is not
heard
→
Go to item B-4.
Fault code No. 37
Item
A
Component other than ISC (Idle Speed Control) unit is defective
(ISC operating sound is heard).
B
Defective ISC (Idle Speed Control) unit (ISC operating sound is
not heard).