Yamaha YZF-R125 Service Manual: Checking the starter motor operation

Yamaha YZF-R125 Service Manual / Electrical system / Electrical components / 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 rectifier/regulator
1. Check: Rectifier/regulator output voltage Out of specification → Replace the rectifier/ regulator. a. Set the engine tachometer to the spark plug lead. b. Connect the pocket tester (DC 20 V) to the rectifier/regulator coupler as shown. Positive tester probe red "1" Negat ...

Checking the crankshaft position sensor
1. Disconnect: Crankshaft position sensor coupler (from the wire harness) 2. Check: Crankshaft position sensor resistance Out of specification Replace the crankshaft position sensor/stator assembly. a. Connect the pocket tester ( × 100) to the crankshaft position sensor c ...

Tachometer
Tachometer Tachometer Tachometer red zone The electric tachometer allows the rider to monitor the engine speed and keep it within the ideal power range. When the key is turned to "ON", the tachometer needle will sweep once across the r/min range and then return to zero r/min ...