Q: Battery light

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I have a rebuilt transmission, new altinator and battery but when I start the car it starts right up. But when it's on the battery light comes on i dont know what else to do or what can be causing the light to still come on
My car has an automatic transmission.

Hello. This may be caused by a faulty ground connection or potentially a bad voltage regulator. Try checking to be sure you have a good connection from the battery to the car’s chassis (black negative battery cable from the battery to the chassis). The voltage regulator is a unit that is responsible for regulating the voltage charge from the alternator to the battery. When this is not working properly, it can undercharge or overcharge the battery causing the battery light to come on. I would recommend having an expert from YourMechanic come to your home to diagnose and test your voltage regulator.

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