Yamaha YZF-R125 Service Manual: Troubleshooting

If the fuel pump fails to operate.

NOTE:

  • Before troubleshooting, remove the following part(s):

1. Rider seat

2. Fuel tank

Troubleshooting


    Circuit diagram
    4. Main fuse 5. Main switch 9. Battery 17.Engine stop switch 25.ECU (engine control unit) 30.Fuel pump 64.Ignition fuse ...

    Electrical components
    1. Main switch 2. Clutch switch 3. Front brake light switch 4. Ignition coil 5. Throttle body sensor assembly (intake air pressure sensor, intake air temperature sensor, throttle position se ...

    Other materials:

    Removing the throttle body
    1. Extract the fuel in the fuel tank through the fuel tank filler hole with a pump. 2. Disconnect: Fuel hose WARNINGCover the fuel hose connections with a cloth when disconnecting them. Residual pressure in the fuel lines could cause fuel to spurt out when removing the h ...

    Checking the piston pin
    1. Check: Piston pin Blue discoloration/grooves  Replace the piston pin and then check the lubrication system. 2. Measure: Piston pin outside diameter "a" Out of specification Replace the piston pin. 3. Measure: Piston pin bore diameter "b" Out of specifica ...

    Supporting the motorcycle
    Since this model is not equipped with a centerstand, follow these precautions when removing the front and rear wheel or performing other maintenance requiring the motorcycle to stand upright. Check that the motorcycle is in a stable and level position before starting any maintenance. A ...

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