Back to all

Alternator Facts (Failing Alternator)

May 16, 2021

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!

Tuffy Bloomington
1505 East Vernon Avenue
Bloomington, Illinois 61701
309.662.0537

More articles from Tuffy Bloomington

Flat Tire? Three?s the Charm (Tire Repair)

March 9, 2025

For most drivers, at some point youre going to have a flat tire. Depending on how it was damaged, it may have to be replaced. But sometimes, a repair will do the trick, as long as the puncture isnt on the sidewall and the hole is smaller than inch/6.35mm in diameter. Here are the three common w... More

Differential Essential (Differential Fluid Exchange)

March 2, 2025

What's the dif? To an automotive technician, it's the differential, a part of your vehicle that helps direct power from the engine to the wheels. The differential is a gearbox that enables the drive wheels to turn at different speeds (they do that when you turn). Inside the differential is a f... More

Clean Slate (Protecting Vehicle's Finish)

February 23, 2025

Winter is one of the hardest times to keep your vehicle clean. But did you know neglecting to wash your vehicle in winter could cost you a significant amount of money in the long run? Here's why. Many areas deal with snow and ice in the winter, and the salt and sand that are used to keep the road... More