Back to all

Alternator Facts (Failing Alternator)

April 3, 2022

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!

Gary Knurek GoodYear
1973 Livernois
Troy, Michigan 48083
248-362-0350

Need Service?

Request a Quote

More articles from Gary Knurek, Authorized GoodYear Dealer

Control Arms: Small Part, Big Impact

July 19, 2026

Heres one part of your vehicle you may never have heard of: the control arm. Its the part that connects the wheel hub and steering knuckle to your vehicles frame. What it does is lets your wheel move up and down while keeping it aligned with your vehicle. Most control arms have things called ... More

No Shake, Just Smooth

July 12, 2026

When your vehicles wheels are out of balance, theyll likely give you some clues. Your steering wheel might shake, the floor or seat vibrates and you might find your vehicle pulling to one side. Other signs? Your tires might wear unevenly and may make odd noises. Plus, fuel economy might not be ... More

Stop Right There!

July 5, 2026

Your vehicles brakes are only as good as its master cylinder. This part is truly is the heart of your braking system, because if it isnt working the way it should, the rest of the brake system cant either. The master cylinder is what takes the pressure you put on the brake pedal and ultimately... More