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Q: Replaced alternator, still not charging battery.

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Battery light and amp gauge show no charge. Replaced alternator, charged for 3 minutes, then no charge again. Could it be solenoid.

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

It sounds like you could have a faulty voltage regulator. When the voltage regulator is not working properly, this may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. In some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. 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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