Back to all

Alternator Facts (Failing Alternator)

December 14, 2025

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 Libertyville
311 South Milwaukee Avenue
Libertyville, IL 60048
8478738044
http://carfixlibertyville.com

Need Service?

Request a Quote

More articles from Car Fix - Libertyville

Car Fix Libertyville Automotive Tips: Alternator

January 25, 2026

Your alternator makes electricity to start and run your engine and all of the vital electrical systems in your vehicle. Thats everything from the on-board computers to the turn signals. And of course there is the entertainment system, seat heaters, power windows and everything you plug into the p... More

Wasteful Thinking

January 18, 2026

With the weather getting colder, you might be tempted to start your vehicle up, let it idle for 15 or 20 minutes and then get in the nice, cozy cabin. Some vehicles offer remote starting that let you do that from the comfort of your home or apartment. But is letting your vehicle idle like that ... More

See the Light (Bulb Replacement)

January 11, 2026

When you notice one of your headlights has gone out, its important for the safe operation of your vehicle to get it changed and working again. Not only is replacing a headlight important for your ability to see in the dark, but its also vital that it be lighting your way and aimed correctly so o... More