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Q: Car battery light constantly goes on and off.

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I go to start my car by a boost. Once the car is started and boost cables are taken off the car battery light comes on, revs up on its own till battery light goes back off, then repeats the same process. Sometimes she even shuts off.

However, when the car is still running and we take the battery posts off, the alternator is able to run the car fine on its own. Many people tell me different things from; battery problems, alternator problems, and even wiring problems.

More information would be great!

My car has 180000 miles.
My car has an automatic transmission.

A: Hello. The fact that the car struggles when...

Hello. The fact that the car struggles when you take the jumper cables off suggests that the battery is not able to maintain a charge on its own. I would recommend checking the alternator and the voltage regulator as these two components work together to maintain the battery charge. I suggest having an expert from YourMechanic come to your home or office to diagnose the battery light and make the necessary repairs.

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