Yamaha MBK XMAX 2014 Service Manual page 373

Fault code No.
Item
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 bro-
ken terminals and locking
condition of the pins).
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 Installed condition of ISC
(idle speed control) unit.
Check for looseness or
pinching.
6 ISC valve is not moving cor-
rectly.
7 Malfunction in ECU.
8 Delete the fault code.
TIP
• Do not remove the ISC (idle speed control) valve.
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).
Improperly connected →
Connect the coupler secure-
ly or replace the wire har-
ness.
Improperly connected →
Connect the coupler secure-
ly or replace the wire har-
ness.
Open or short circuit → Re-
place the wire harness.
Between ISC (idle speed
control) unit coupler and
ECU coupler.
pink–pink
light green–light green
green–green
sky blue–sky blue
Improperly installed ISC (idle
speed control) unit → Rein-
stall the ISC (idle speed con-
trol) unit.
Replace the throttle body as-
sembly.
Replace the ECU.
8-60
FUEL INJECTION SYSTEM
Execute the diagnostic
mode. (Code No. D54)
ISC operating sound is heard
→ Go to item 8.
ISC operating sound is not
heard → Go to item 3.
Execute the diagnostic
mode. (Code No. D54)
ISC operating sound is heard
→ Go to item 8.
ISC operating sound is not
heard → Go to item 4.
Execute the diagnostic
mode. (Code No. D54)
ISC operating sound is heard
→ Go to item 8.
ISC operating sound is not
heard → Go to item 5.
Execute the diagnostic
mode. (Code No. D54)
ISC operating sound is heard
→ Go to item 8.
ISC operating sound is not
heard → Go to item 6.
Execute the diagnostic
mode. (Code No. D54)
ISC operating sound is heard
→ Go to item 8.
ISC operating sound is not
heard → Go to item 7.
Start the engine and let it idle
for approximately 10 sec-
onds.
Check that the fault code
number is not displayed.