Q: Battery light on while driving but then goes off?

asked by on December 05, 2016

I started my car tonight and my parking brake light comes on and my battery light comes on. Then when I go to drive it goes off but I get halfway down the street and it comes back on why is this?

My car has 187000 miles.
My car has an automatic transmission.

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The battery light indicates that your charging system has a flaw in it which may be a sign of a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator is responsible for charging the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator. 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 as you have described. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your charging system.

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