If your multimeter has a beep function (or what ever it's called), place one probe to the relay socket and other to the good ground. Now you should have constant beeeep from the multimeter. Then just start pulling the harnes, and when the beep goes away, you're close.

 

Hey all. I’m back with no solution still. Before searching for the potential short, I did the smart thing and rechecked to see if the ground continuity changed when turning the car on. And I don’t know what I was looking at before, but shifting the key into the “on” position most definitely got rid of the ground trace.

In the meantime, I have ordered a new PCM hoping that could fix it and knowing there is some lead time to get it programmed.

if anyone has any other ideas - feel free to throw it out there! Thanks again.

 

You should be able to swap the PCM from another truck. I found one with the same part number for my '96 Ram. Unplugged the old one and plugged in the new/used one and the truck started right up. If you find a PCM with the same part number as the existing one on your truck, it should be plug and play for that year truck.