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Q: Battery light flashing at low rpm basically at idle my battery light flashes

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I replaced battery terminals and come grounds and replaced the fuse but my battery light flashes at low rpms basically at idle and goes away when I give it gas I replaced my alternator belt the battery light gets solid when I use more accessories could that be my alternator I got it tested at autozone but they told me is was good but they didn't test the alternato directly just hooked up a battery tester that's it please help me with this

My car has 203687 miles.
My car has an automatic transmission.

Hi There, You may have a failing voltage regulator that could be allowing the alternator to fluctuate too much resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. If the charging ability of the alternator is not maintained, this may cause a fluctuation in the power as you have described. 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. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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