Yamaha YZF-R125 Service Manual: 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".

WARNING
  • A wire that is used as a jumper lead must have at least the same capacity of the battery lead, otherwise the jumper lead may burn.
  • This check is likely to produce sparks, therefore, make sure no flammable gas or fluid is in the vicinity.

Checking the starter motor operation


b. Check the starter motor operation.

    Checking the lean angle sensor
    1. Remove: Lean angle sensor 2. Check: Lean angle sensor output voltage Out of specification Replace. a. Connect the lean angle sensor to the wire harness. b. Connect the pocket tester ...

    Checking the stator coil
    1. Disconnect: Stator coil coupler (from the wire harness) 2. Check: Stator coil resistance Out of specification → Replace the crankshaft position sensor/stator assembly. a. Conne ...

    Other materials:

    Checking the primary driven gear
    1. Check: Primary driven gear "1" Damage/wear Replace the primary drive gear and clutch housing as a set. Excessive noise during operation  Replace the primary drive gear and clutch housing as a set. ...

    Checking the turn signal relay
    1. Check: Turn signal relay input voltage Out of specification →The wiring circuit from the main switch to the turn signal relay coupler is faulty and must be repaired. a. Connect the pocket tester (DC 20 V) to the turn signal relay terminal as shown. - Positive tester probe  b ...

    Lubricating the drive chain
    The drive chain consists of many interacting parts. If the drive chain is not maintained properly, it will wear out quickly. Therefore, the drive chain should be serviced, especially when the vehicle is used in dusty areas. This vehicle has a drive chain with small rubber O-rings between eac ...

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