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Is It The Battery Or The Alternator? 

Battery Or Alternator?

Have you ever been in a hurry to get somewhere, run out the door to get in the car, and it didn’t start? If yes, then you know how incredibly frustrating it is!

The usual assumption in this scenario is that your battery is dead. But what if it isn’t? It could be your alternator causing your car not to start.

How Do I Check My Battery?

If your car doesn’t start, the first thing you should check is the battery. Start by inspecting the battery surroundings, especially the terminals. You will want to ensure that they are clear of corrosion and that the cables are properly connected. The battery cables cannot make a good connection if there is excess corrosion. If you need to clean the terminals, disconnect the battery cables and use baking soda and a wire brush.

What if corrosion isn’t present on the battery? You will need to check the voltage of your battery using a multimeter. When the car runs, the voltage should be approximately 14-15 volts. When the vehicle is off, the voltage should be about 12 volts. Any readings outside of the above may suggest a bad battery.

How Do I Check My Alternator?

You found no issues with your battery; it is time to check the alternator (this part recharges your battery as the vehicle runs). Newer cars have an internal diagnostic system that will tell you when certain parts fail. You can see these diagnostics using a code reader if you have one. Assuming you don’t have a code reader handy, there is another way you can test your alternator.

Start your car; if you can get your vehicle to run temporarily. Then disconnect the positive battery terminal. If disconnecting the positive terminal causes the car to stop running, you have an alternator issue.

What If My Battery And Alternator Are Not The Problems?

Another issue that may cause your vehicle not to start could be the starter itself. Power is sent to the starter when you put your key in the ignition or push the button in many newer vehicles.

If your vehicle doesn’t crank when you turn the key in the ignition, your starter is bad and will need to be replaced.

Tilly Mill Auto Center Can Help

We offer free battery and charging system tests and can help diagnose and repair any problems. Stop by and let us help you keep your vehicle in good working condition.

Tilly Mill Auto Center is a Family Owned and Operated, Full-Service Auto Repair Shop.

Convenient to Doraville, Dunwoody, Chamblee, Johns Creek, Norcross, Peachtree Corners and Brookhaven.

Hours and Payment

Payment Forms Accepted: Credit Card, Cash – No Personal Checks

Business Hours:

  • Weekdays: 7am – 6pm
  • Saturday: Closed
  • Sunday: Closed