Yamaha YZF-R125 Service Manual: Circuit diagram

Charging system

...

Troubleshooting

The battery is not being charged. NOTE: Before troubleshooting, remove the following part(s): 1. Rider seat 2. Left side panel 3. Left lower side cowling ...

Other materials:

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 ...

Faulty lighting or signaling system
Headlight does not come on - Wrong headlight bulb - Too many electrical accessories - Hard charging - Incorrect connection - Improperly grounded circuit - Poor contacts (main or light switch) - Burnt-out headlight bulb Headlight bulb burnt out - Wrong headlight bulb - Faulty battery - Fau ...

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 ...