Q: Battery light turned on while I was driving

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My battery light turned on while driving. I got home, checked it and drove to the store and back but light hasn't turned on again. Should I be concerned even if light isn't on anymore?

This may be a sign of a failing voltage regulator, a weak battery 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. Often times this will result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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