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:

    Checking the fuses
    The following procedure applies to all of the fuses. CAUTION:To avoid a short circuit, always turn the main switch to "OFF" when checking or replacing a fuse. 1. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 2. Check: Fuse a. Connect the pocket te ...

    Checking the steering head
    1. Wash: Bearings Bearing races 2. Check: Bearings Bearing races Damage/pitting →Replace. 3. Replace: Bearings Bearing races a. Remove the bearing races from the steering head pipe with a long rod "1" and hammer. b. Remove the bearing race from the lower bracket ...

    Checking the starter motor operation
    1. Check: Starter motor operation Does not operate → Perform the electric starting system troubleshooting, starting with step 4. Refer to "TROUBLESHOOTING" on page 8-9. a. Connect the positive battery terminal "1" and starter motor lead "2" with a jumper lead "3". W ...

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