The Power Behind your Engine (Alternator Diagnosis and Repair)
September 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.
Sterling Tire & Auto
34701 Van Dyke Rd
Sterling Heights, Michigan 48312
586-264-7775
Need Service?
More articles from Sterling Tire & Auto

Leaking Oil Isn’t Normal: When a Valve Cover Gasket Needs Replacing
October 4, 2026
Lets say you discover a little oil leak in your vehicle and you think, Its small. Its no big deal. Remember that no oil leak is ever normal, and it might be a sign that your valve cover gasket is failing. That gasket is what seals the top of your engine. It keeps oil inside while your engine ... More

Smooth Operator
September 27, 2026
Were used to bringing a vehicle to a stop and hardly noticing the engines even running when were sitting still. But sometimes you might notice it running rough when youre idling. Your vehicle is shaking, vibrating and making sputtering noises. You may even notice the tachometer on your instrum... More

Keep Cool: Why Radiator Hoses Matter
September 20, 2026
If theres one thing you want to make sure is going on under your vehicles hood, its that your engine doesnt get too hot. Heat is an engines worst enemy, and it can result in very expensive repairs, even leave you stranded in a tough spot. One vital part of your vehicle is the radiator hose, whic... More
