Back to all

The Power Behind your Engine (Alternator Diagnosis and Repair)

December 20, 2020

There's nothing like that sinking feeling when you turn the key and nothing happens in your vehicle.  A lot of us are quick to blame the battery.  But it may instead be your alternator that's failing.

Your battery supplies power to start your vehicle, but the alternator is what sends power when your engine is running.  The good news is alternators last a fairly long time, and it's not unusual to get seven years out of one. But they can give up the ghost thanks to the harsh conditions in the engine compartment.

Alternators have bearings inside them that keep things turning smoothly.  Debris, liquid, dirt and more can team up with the high temperatures your engine generates to cause those bearings to seize up.  That's not good, and if that happens, you may even be able to hear the bearings grind.

Other symptoms of a dying alternator are a squealing noise in the engine compartment or your headlights may go dim and bright, dim and bright.  You might even notice an electrical smell.  Any of these signs warrants a trip to your service facility.

Here's something else to think about.  If your alternator's bearings have seized up and the unit's shaft is not turning freely, that can destroy the belt that's attached to it.  So don't be surprised if your service advisor says both parts have to be replaced. 

There are different grades of alternators you can buy, but consider just how important this part is to keep your vehicle running.  Your service advisor will give you options based on your driving style and vehicle.  Remember, if you notice any of those symptoms that may signal a failing alternator, have it taken care of before you wind up stuck somewhere at the side of the road.

Tuffy Tire & Auto Service Glendale Heights
1153 Bloomingdale Rd.
Glendale Heights, Illinois 60139
630-588-8846

More articles from Tuffy Glendale Heights

Strutting Your Stuff (Shocks and Struts)

June 29, 2025

Ever wonder how your vehicle is able to move over bumps, potholes and other irregularities in the road and you hardly feel a vibration in the cabin? Its your shocks and struts doing the hard work along with the rest of your suspension and tires. They keep the ride smooth and are important for yo... More

When Your Air Bag Light Comes On (Illuminated Air Bag Light)

June 22, 2025

There are some dashboard lights you should pay more attention to than others. One is the air bag light. If it's on and your vehicle is in an accident, your air bags probably won't do their job. Automakers began installing air bags in the late 1990's since they were mandatory in the United State... More

Avoiding Exhaustion (EGR Valve Replacement)

June 15, 2025

No, ERG isnt the sound a pirate makes. Its a part in your vehicle that recirculates exhaust gas to reduce certain gases and pollutants in the atmosphere. In fact, ERG stands for Exhaust Gas Recirculation. One gas our vehicles may make when they burn fuel is nitric oxide, which can play a big ro... More