Have a 2005 Dodge Ram 1500 5.7 Hemi, alternator not holding a charge so it is draining the battery. replace alternator 2 times. was told that the regulator is inside the PCM. What can we do?
The alternator doesn't hold a charge, the battery does. With the truck running, what is the voltage across the battery, should be 14v or more. If it is, the alternator is working fine. The voltage Regulator is in the alternator. Seems you have a electrical draw/parasitic drain on your battery. You will need to do some investigative work by pulling fuses, looking for loose, cut wires, corrosion and probing for continuity. I suspect you might be better off having someone who is good with Auto Electrics to diagnose it for you, it can be very time consuming and frustrating if you don't know what you are doing.
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