Yamaha MBK MW125 2014 Service Manual

FUEL INJECTION SYSTEM8-36Fault code No. 191 Installed condition of throttle po-sition sensor.Check for looseness or pinch-ing.Make sure that the mountingposition is corrected.Turn the main switch to “ON”and operate the throttle valveopen and close.Fault code number is not dis-played → Service is finished.Fault code number is displayed→ Go to item 2.2 Defective throttle position sen-sor.Execute the diagnostic mode.(Code No. 01)When the throttle valve is fullyclosed:A value of 14–20 is indicated.When the throttle valve is fullyopen:A value of 97–107 is indicated.Replace the throttle body, if de-fective.Turn the main switch to “ON”and operate the throttle valveopen and close.Fault code number is not dis-played → Service is finished.Fault code number is displayed→ Go to item 3.3 Malfunction in ECU Replace the ECU.Refer to “REPLACING THEECU (engine control unit)” onpage 8-59.Fault code No. 16Item Throttle position sensor is stuck.Fault code No. 19Item Sidestand switch: a break or disconnection of the blue/yellow lead ofthe ECU is detected.Fail-safe system Unable to start engineUnable to drive vehicleDiagnostic code No. 20Tool displaySidestand switch• “ON” (sidestand retracted)• “OFF” (sidestand extended)Procedure Extend and retract the sidestand (with the transmission in gear).Item Probable cause of malfunc-tion and check Maintenance job Confirmation of service com-pletion1 Connection of sidestand switchcoupler.Check the locking condition ofthe coupler.Disconnect the coupler andcheck the pins (bent or brokenterminals and locking conditionof the pins).Improperly connected → Con-nect the coupler securely or re-place the wire harness.Turn the main switch to “ON”,and then extend and retract thesidestand.Fault code number is not dis-played → Service is finished.Fault code number is displayed→ Go to item 2.2 Connection of wire harnessECU coupler.Check the locking condition ofthe coupler.Disconnect the coupler andcheck the pins (bent or brokenterminals and locking conditionof the pins).Improperly connected → Con-nect the coupler securely or re-place the wire harness.Turn the main switch to “ON”,and then extend and retract thesidestand.Fault code number is not dis-played → Service is finished.Fault code number is displayed→ Go to item 3.