The alternator is part of your vehicle's electrical system. Its main function is to provide power to operate the starter fire and all electronic accessories in your car. If your alternator starts to go bad, you may notice that your headlights and/or dashboard lights start to dim. Once the dash lights or headlights dim, this is a clear sign of potential alternator failure. A fading AC may cause other electronic accessories, such as power windows and/or power seats, to operate more slowly than usual.
How to tell if a car alternator is broken。
How to tell if a car alternator is broken
When the car does not start, use a meter to measure the voltage of the battery and record it. Then start the car, measure the battery voltage with an electric meter, and record it. If the car's alternator is not broken, the battery voltage will be higher when the car is started, about 13.5V. But it will definitely be higher than the voltage number at which the car won't start. If the car alternator breaks down, the voltage of the battery will be lower than before it was started. The most obvious thing about a broken car alternator is that if the alternator is broken, the battery will lose power soon after the car is driven and the car will not be able to start.
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