Q: Q: Battery light on

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The battery light has been blinking on and off for the last couple of months. Tonight while I was driving, all the lights came on my dash board. The brake light was on too and the hand brake wasn't even on. I could barely drive the car. I was almost home so I just drove it home and parked it on the driveway. Do I need a new alternator? How much will that be?

My car has 136000 miles.
My car has an automatic transmission.

It sounds like you may have a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power. When the voltage drops below a certain level, this may also cause other lights to come on such as the brake light. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

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