Alternator voltage test

Connect a voltmeter between the positive (+) and negative (-) battery poles.

Start the engine. When starting the engine, the voltage should not fall below 9.5 volts.

Increase the engine speed to 4000 rpm. In this case, the voltage should be from 13.7 to 14.6 volts. This is proof that the generator and relay-regulator are working properly.

Check the stability of the voltage regulation To do this, turn on the main beam and repeat the measurement at an engine speed of 4000 rpm. The measured voltage value should not exceed the previously obtained value by more than 0.4 volts.

If the measured values are outside the prescribed values, have the generator serviced by a workshop.