Yamaha YZF-R125 Service Manual: Circuit diagram

Circuit diagram


2. Crankshaft position sensor

4. Main fuse

5. Main switch

6. Radiator fan motor fuse

8. Sidestand switch

9. Battery

17.Engine stop switch

19.Intake air pressure sensor

20.Intake air temperature sensor

21.Throttle position sensor

22.Coolant temperature sensor

23.Lean angle sensor

24.Self-diagnosis signal connector

25.ECU (engine control unit)

26.Ignition coil

27.Spark plug

28.FID (fast idle solenoid)

29.Fuel injector

30.Fuel pump

32.Radiator fan motor relay

33.Radiator fan motor

63.Engine trouble warning light

64.Ignition fuse

66.Signaling system fuse

67.Speed sensor

    Fuel injection system
    ...

    Ecu self-diagnostic function
    The ECU is equipped with a self-diagnostic function in order to ensure that the fuel injection system is operating normally. If this function detects a malfunction in the system, it immediately o ...

    Other materials:

    Throttle position sensor
    1. Check: Throttle position sensor a. Connect the digital circuit tester to the terminals of the throttle body sensor assembly coupler as shown. Positive tester probe → gray/red terminal "1" Negative tester probe → gray/black terminal "2" b. Measure the throttle pos ...

    Troubleshooting
    Any of the following fail to light: turn signal lights, brake light or indicator lights. The horn fails to sound. The fuel gauge fails to operate. The speedometer fails to operate. NOTE: Before troubleshooting, remove the following part(s): 1. Seats 2. Fuel tank 3. Left upper ...

    Checking and lubricating the brake and shift pedals
    Brake pedal Brake pedal Shift pedal Shift pedal The operation of the brake and shift pedals should be checked before each ride, and the pedal pivots should be lubricated if necessary. Recommended lubricant:Lithium-soap-based grease ...

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