Back to all

The Power Behind your Engine (Alternator Diagnosis and Repair)

March 15, 2026

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.

ServicePro Quick Lube
3165 I 75 Business Spur
Sault Sainte Marie, MI 49783
9066353018

More articles from Service Pro Quick Lube

A Hot Mess (AC System-Compresser)

June 14, 2026

Air conditioning used to be a real luxury in a vehicle, but now it's standard in most. Your vehicle's air conditioning system is built to last a pretty long time, but like anything mechanical, sometimes it fails. It helps to know a little about how the A/C works. There's a compressor that pres... More

Automotive Tips from ServicePro Quick Lube: Brake Noise

June 7, 2026

Your brake pads are the important parts that rub against the rotor (or disc) to slow and stop your car when driving in Sault Sainte Marie. They eventually wear down.When your pads are worn too much, they wont stop your vehicle as well. When the friction material is worn away, metal parts of the p... More

If the Shoe Fits (Brake Shoe Replacement [Rear])

May 31, 2026

When it comes to brakes on your vehicle, we all know how important it is to keep them working well because they are vital safety equipment. After all, if you cant slow down and stop, you cant drive safely. While many vehicles use what are called disc brakes, theres another type of brakes that ... More