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Q: Car won't start, battery light on

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My car battery light comes on when car is off. Battery dies overnight. First time jumped it an it did fine after that had to get a jump to get juice but solenoids had to be crossed to get started put a new ignition switch on because everybody kept telling me that was the problem. Didn't work. Somebody jiggled the fuse box an wires under hood the light went off it started drove it home 40 min drive. Turned it off light came back on. I tried to jiggle press n all that n didn't work for me. Had alternator checked it isn't bad change battery to a new one still same thing cleaned connectors to battery. Its so frustrating an I have to work it's been down for 3 weeks

My car has 200000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. This may be related to what is called a voltage regulator. This is a unit that monitors the charging of the battery by the alternator. When this is not working properly, this can cause the alternator to sometimes overcharge or undercharge the battery or in some cases not charge it at all. I would recommend having an expert from Your Mechanic come to your home to diagnose and test your voltage regulator and check your ground connections.

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