Where do I find the voltage regulator on a 1999 dodge ram 1500 pickup

 

The voltage is regulated by the PCM.

 

X2, always good to verify your battery terminals are clean and the PCM power supply/ground is good, same with alternator, after that pretty much SOL, REMAN PCM or external voltage regulator, that is if your alternator bench tests good

 

Or, a used PCM. Match up the part number to the one on your truck. For that year, I believe you might also need to have the VIN in the PCM changed to match the VIN of your truck, but that would be it. I keep a couple on hand for my '96, as they are pretty much plug and play as long as I get the PCM with the right part number. The external voltage regulator option can be done, but does take some wiring and work.