The Power Behind your Engine (Alternator Diagnosis and Repair)
September 13, 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.
Commerce Auto Repair
9575 Commerce Rd.
Commerce, Michigan 48382
248.363.3749
Need Service?
More articles from Commerce Auto Repair

Stop Right There!
October 25, 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

A Smart Inspection, Peace of Mind Before You Buy
October 23, 2026
With the price of new vehicles these days, you might be thinking about saving some money by buying a used one. But when you go to look at a vehicle, how in the world do you know what youre getting into? A look around the outside and a short test drive likely doesnt give you the confidence that... More

Save Your Tires and Fuel: Why TPMS Is More Than a Warning Lightc
October 11, 2026
You know that little light on your dashboard that looks like a tire? Dont ignore it. Its a lot more than a warning light. Its trying to tell you something that can protect your tires, improve your fuel economy and keep your vehicle traveling safely down the road. Its called TPMS. The abbreviati... More
