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Q: PCM

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Bought a new PCM put it in right about 30 miles and same systems I had again not charging my alternator battery going dead voltage radiator it's not charging my battery what causes a PCM to go out

My car has 12833 miles.
My car has an automatic transmission.

A: It sounds like the voltage regulator may be...

It sounds like the voltage regulator may be overcharging causing it to essentially electrocute the PCM. As you may know, the voltage regulator regulates the voltage in the system by not allowing the alternator to over charge the battery. As you may know, the alternator is responsible for charging the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator. The voltage regulator 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 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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