Yamaha YZF-R125 Service Manual: Troubleshooting

The starter motor fails to turn.

NOTE:

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

1. Seats

2. Fuel tank

3. Left lower side cowling

4. Left upper side cowling

Troubleshooting


Troubleshooting


    Starting circuit cut-off system operation
    If the engine stop switch is set to " " and the main switch is set to "ON" (both switches are closed), the starter motor can only operate if at least one of the following conditions is met: ...

    Charging system
    ...

    Other materials:

    Troubleshooting
    The ignition system fails to operate (no spark or intermittent spark). NOTE: Before troubleshooting, remove the following part(s): 1. Seats 2. Fuel tank 3. Right side cover 4. Left side panel 5. Left upper side cowling ...

    Intake air pressure sensor
    1. Check: Intake air pressure sensor output voltage Out of specification Replace the throttle body. a. Connect the pocket tester (DC 20 V) to the throttle body sensor assembly coupler as shown. Positive tester probe pink/white "1" Negative tester probe gray/black "2" ...

    Checking the spark plug cap
    1. Check: Spark plug cap resistance Out of specification Replace. a. Remove the spark plug cap from the spark plug lead. b. Connect the pocket tester ( × 1k) to the spark plug cap as shown. c. Measure the spark plug cap resistance. ...

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