What Does an Alternator Do?

Car Alternator


Your vehicle’s alternator powers all of your electronics as you drive through Bloomfield Hills. While some may have thought that their battery powers their vehicle’s electronic system, this is actually a shared responsibility between these two components. The battery in your vehicle powers electronics while the engine is off, but as soon as the engine is turned on the alternator takes over this task. 

The alternator functions as a small generator that uses your car’s gas engine as its source of energy. Learn more about what an alternator does and how much a new alternator is with the service team at Fred Lavery Porsche Company below!

Do I Have a Bad Alternator?

If you’re worried that your alternator may need to be replaced, there are a few signs you can check for. Read them below:

  • Battery warning light appearing on the dashboard
  • Dim headlights or interior lights as you drive through Rochester Hills
  • Burning rubber smell under the hood
  • Devices not charging
  • Whining or screeching sound after the vehicle has started
  • Unable to start

If you notice any of the above signs, schedule a service appointment at Fred Lavery Porsche Company to have your alternator inspected by our team!

Failing Alternator vs. Battery

Since your vehicle’s alternator and battery share many of the same duties, it can be difficult to tell when your vehicle’s battery is failing vs. the alternator. There are a couple of ways to determine which component needs replacing: 

  • Get in your vehicle and turn the headlights on without starting the car. If the headlights are dim, then you need a new battery. 
  • If the headlights are strong, start the car and watch the lights. If the lights fade in and out, then your alternator will need to be replaced. 

Another way to see if the battery or alternator needs to be replaced is to wait until your vehicle needs a jump-start. Once you’ve jump-started your vehicle, remove the cables from your battery. If your vehicle dies immediately, then your alternator needs to be replaced. 

How Much is an Alternator?

Most alternators will last between 80,000 and 150,000 miles — or about seven years. However, your driving habits and the area where you live could wear it out prematurely. When that happens you’ll need to buy a new alternator to keep your Porsche running smoothly on Bloomfield Hills roads. How much is an alternator? On average a new Porsche alternator will cost between $500 and $2,500, but the final cost will depend on the type of vehicle you drive. You can find a new alternator when you order from our parts department.

Visit Fred Lavery Porsche Company for a New Alternator 

If you need a new alternator or you just want your alternator inspected, you can count on the Fred Lavery Porsche Company service team! We’ll help you save on your next service visit while we ensure that your Porsche is running stronger than ever. You can also contact us with any questions you have. We look forward to helping your Porsche run mile after mile in Birmingham!


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Fred Lavery Porsche Company 42.542627, -83.2083085.