Alternator Facts (Failing Alternator)
November 19, 2023
If you notice that your headlights are flickering at night, that's something to pay attention to. While there could be many different things that could cause that problem, one possibility is your vehicle's alternator.
The alternator takes mechanical energy from the engine and turns it into electricity, in essence a generator. The current it makes charges the battery and supplies power to the vehicle's electrical systems. An alternator is made up of several different parts: a pulley, magnets, coil wires, brushes and a voltage regulator. While your vehicle is running, these parts get a good workout and, after time, they begin to wear out.
Other symptoms of a failing alternator include your vehicle's lights dimming, the power windows going up and down more slowly than they used to, your power seats not moving quite as fast as before.
Another sign of a worn out alternator is engine stalling. Vehicles with fuel injection require a certain amount of power, and when an alternator is going bad, your engine could stall because the alternator isn't cranking out enough of it.
An alternator on its last legs can also fail to charge your battery properly. Sometimes your battery isn't getting enough charge from the alternator and will go dead. It also can be the opposite problem. The battery is getting too much power and will cause the battery to get hot. Your vehicle may give you a clue on the instrument panel. If you see any of these warning lights, take note: Check Engine, ALT, CHARGE or one that looks like a picture of a battery. If that light is on, it's time to have your service facility give it a look.
As mentioned earlier, there are other components of your vehicle's electrical system that can fail, such as a worn out serpentine belt or a malfunctioning voltage regulator. A reputable service facility has diagnostic tools to pinpoint the causes of your problems. And when your issues are fixed, your electrical system will be back to its hard-working self. You'll get a real charge out of it!
Car Fix Shelby
46870 Van Dyke Ave.
Shelby Township, Michigan 48317
(586) 739-7810
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