When a voltage regulator is bad, the voltage output will fluctuate. To tell if the output is abnormal, check the car manual to find the correct voltage range for the car.
To test a voltage regulator, purchase a voltage meter. Connect the positive and negative ends of the meter to the positive and negative terminals on the battery. Turn the car on and push down on the accelerator to get a reading.
A voltage regulator is a mechanical part that regulates the voltage of electrical equipment in a car. The voltage regulator is also responsible for meeting the charging requirements of the battery.