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:

    Engine specifications
    ...

    Checking the thermostat
    1. Check: Thermostat Does not open at 80.5-83.5 C (176.9-182.3 F)  Replace. a. Suspend the thermostat "1" in a container "2" filled with water. b. Slowly heat the water "3". c. Place a thermometer "4" in the water. d. While stirring the water, observe the thermostat and th ...

    Installing the drive chain
    1. Lubricate: Drive chain Master link 2. Install: Drive sprocket Drive sprocket retainer bolts 3. Install: Master link O-rings Master link plate Master link clip "1" CAUTION: The closed end of the master link clip must face in the direction of drive ch ...

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