Yamaha MBK MW125 2014, Service Manual

Page: 336 / 380

FUEL INJECTION SYSTEM
8-39
Fault code No. 24
1 Connection of throttle body sen-
sor assembly 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.
Turn the main switch to “ON”.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item 2.
2 Connection of wire harness
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.
Turn the main switch to “ON”.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item 3.
3 Wire harness continuity. Open or short circuit
→
Replace
the wire harness.
Between throttle body sensor
assembly coupler and ECU
coupler.
brown/white–brown/white
black/blue–black/blue
Turn the main switch to “ON”.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item 4.
4 Installed condition of throttle
body sensor assembly.
Check for looseness or pinch-
ing. Improperly installed sensor
→
Reinstall the sensor or replace
the throttle body.
Turn the main switch to “ON”.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item 5.
5 Defective intake air temperature
sensor. Execute the diagnostic mode.
(Code No. 05)
When engine is cold:
Displayed temperature is close
to the ambient temperature.
The displayed temperature is
not close to the ambient tem-
perature.
→
Check the air tem-
perature sensor.
Replace throttle body, if defec-
tive.
Turn the main switch to “ON”.
Fault code number is not dis-
played
→
Service is finished.
Fault code number is displayed
→
Go to item 6.
6 Malfunction in ECU. Replace the ECU.
Refer to “REPLACING THE
ECU (engine control unit)” on
page 8-59.
Fault code No. 22
Item Intake air temperature sensor: open or short circuit detected.
Fault code No. 24
Item
O
2
sensor: no normal signals are received from the O
2
sensor.
Fail-safe system
Able to start engine
Able to drive vehicle
Diagnostic code No. —
Tool display —
Procedure —