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Q: Changed alternator and battert, light still on and car dieing

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Changed alternator and battery and light is still on and battery dieing.... what do I do next...which fuses should I check, where is the fuse link and how do I check it? What else could it be?

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

This may suggest a bad grounding issue or potentially a failing voltage regulator. This 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 and properly test your vehicle’s charging system.

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