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Q: Battery not charging with new alternator and serpentine belt

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I am getting an error message that my battery is not charging. I replaced the alternator and serpentine belt. I have 12.5 volts before starting the engine and 11.7 after starting.

Hi There, You may have a faulty voltage regulator which is a component that is responsible for regulating the rate at which the battery is charged by the alternator. When the voltage regulator is not working properly, this may result in an erratic voltage fluctuation causing the battery not to be charged at a consistent rate. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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