Yamaha MBK XMAX 2014 Service Manual page 372

Fault code No.
Item
5 ISC valve is not moving cor-
rectly.
6 Malfunction in ECU.
TIP
• Do not remove the ISC (idle speed control) valve.
• If fault code numbers "37" and "46" are both indicated, take the actions specified for fault code number
"46" first.
• If fault code numbers "37" and "42" are both indicated, take the actions specified for fault code number
"42" first.
Fault code No.
Item
Fail-safe system
Diagnostic code No.
Actuation
Procedure
Probable cause of mal-
Item
function and check
1 Locate the malfunction.
37
Component other than ISC (idle speed control) unit is de-
A
fective (ISC operating sound is heard).
Defective ISC (idle speed control) unit (ISC operating sound is
B
not heard).
Replace the throttle body as-
sembly.
Replace the ECU.
37
Component other than ISC (idle speed control) unit is defective
A
(ISC operating sound is heard).
Defective ISC (idle speed control) unit (ISC operating
B
sound is not heard).
Able to start engine
Able to drive vehicle
D54
Actuates and fully closes the ISC valve, then opens it to the stand-
by opening position when the engine is started.
This operation takes approximately 3 seconds until it is completed.
The ISC unit vibrates when the ISC valve operates.
Maintenance job
Execute the diagnostic
mode. (Code No. D54)
Fully closes the ISC (idle
speed control) valve, and
then fully opens the valve.
8-59
FUEL INJECTION SYSTEM
Start the engine and let it idle
for approximately 10 sec-
onds.
Fault code number is not dis-
played → Service is finished.
Fault code number is dis-
played → Go to item 6.
Confirmation of service
completion
ISC operating sound is heard
→ Go to item 2 in section A
for the component other than
ISC (idle speed control) unit
is defective.
ISC operating sound is not
heard → Go to item 2.