What Causes the Alternator to Go Bad?

If your car is getting hard to start or it stalls unexpectedly, you may be wondering if the problem is caused by a bad battery, a failing car starter, or a bad alternator? Head to your auto shop and have the entire starter system checked out. Even though this system was designed for repeated use under a variety of conditions, normal wear and tear over time, extreme weather and road conditions, or poor maintenance can all cause problems.

If a dead battery or a bad car starter has been ruled out as the cause of your starting problem, you may be left wondering what causes the alternator to go bad? There are several issues that can ruin an alternator:

• Using jumper cables wrong,
• Overloading the charging system with too many accessories,
• Leaking fluid, or
• A tight belt that can damage bearings.

Just what does the alternator do, you ask? Basically, the alternator keeps the battery charged so that it can ignite the car starter. Once the car starts running, the alternator works continuously to keep the battery charged. If the alternator goes bad, the battery will eventually lose its charge and you will not be able to operate your car.

How long should an alternator last? The lifespan of an alternator is generally affected by its quality, how the car is driven, and how many electronic accessories are being used. There is no set service interval for alternators and they can die with little or no warning.

There are a few signs that indicate the alternator is starting to fail:

1. The "ALT" or "GEN" light illuminates on the instrument panel.
2. The lights are dimmer than usual and may pulsate from dim to bright.
3. Other electrical systems, such as power windows, power locks, air conditioning, radio, GPS, etc., will start to act up.
4. Bearings in the engine may fail, creating unusual rattles.
5. The engine will stall as there is not enough power in the spark plugs to start the engine or to keep it running.
6. The battery will lose its charge.

Wondering what causes the alternator to go bad? Contact our ASE Certified Technicians at Cannon Auto Repair for more information about the starting system and to schedule an appointment. Our auto shop serves vehicle owners in Cannon Falls, MN, and the surrounding areas.

About the Author

Jan Udenberg

Jan, is loving wife of our devoted owner Rich Udenberg who passed away unexpectedly in January of 2023. Jan spent 30 plus years as a Laboratory Technician at the Mayo Clinic and recently retired in December of 2022. After Rich passed she joined the team here at Cannon Auto and has enjoyed learning about the automotive industry, meeting our amazing and loyal customers along with seeing what her husband did for so many years here at the shop. She brings her dog Bear with everyday to work and customers seem love our new four legged greeter. Outside of work Jan loves to spend time with her grandkids, spending time at the family cabin; fishing, four-wheeling, snowmobiling and most of all being outside.

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