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Q: Charging system - 1990 Ford F-150

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Problems with charging system. Had batt and alt. tested they said batt was good. Alt was not replaced alt still wont charge

My car has an automatic transmission.

A: Hello. I would suggest checking the voltage...

Hello. I would suggest checking the voltage regulator. This is a unit that monitors the charging system to maintain the proper voltage in the battery by regulating the rate at which the battery is charged. When this is not working correctly, this will sometimes cause the battery to not charge at all or overcharge. This is often times the culprit when the battery and alternator are confirmed to be working properly. If you need to get a second opinion on the system, a certified technician from YourMechanic can come to your car’s location to diagnose the charging issue and let you know what needs repair.

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