Warning Signs Of A Bad Alternator
Because of the alternator’s importance, it’s essential to watch for signs that it may be going bad, in order to avoid a potential breakdown. According to Hatcher, there are two main problems that can occur with the alternator: Either it undercharges or it overcharges itself.
Symptoms of an undercharging or no-output alternator are usually pretty obvious:
- You see a message or warning light, such as a battery light on your dashboard, indicating an issue with the charging system.
- You notice that your dashboard lights are dimming, or your headlights run brighter when you accelerate but then dim when you come to a stop.
- Your battery dies when the car is parked.
- The car doesn’t even attempt to start or “turn over.”
Overcharging happens when an alternator shorts internally and puts out too much voltage. Here are some symptoms in this case:
- If your car’s dash comes equipped with a voltmeter, you notice it showing an overly high voltage: 15 or more volts.
- Your lights can be especially bright when your engine speed increases (they just won’t dim, as they can do with undercharging).
- You hear a loud grinding noise from under the hood. Sometimes heat or dirt can cause wear and eventual breakdown of the small bearings, or bushings, that let the rotor spin smoothly inside the stator. The resulting sound will tell you immediately that something is wrong.