DDD

Hoping someone can give me a hand! I bought a 2002 cummins 5 speed manual in auction. Went to drive the truck home and it started great and idled fine but wouldn't rev over 1100rpm. I figured injection pump. After towing it home while it idled I got home and it would no longer start. Found plug going to in tank lift pump was damaged. Fixed that problem. Long story long I couldn't even get he truck to start even with hot wiring injection pump. I put a refurbished injection pump in and fass fuel system and still won't start. Code P1689. Followed these steps and resistance between ground and term 2 on injection pump measures Overload. Did the injection pump circuit testing and found resistance between ground and N.86 in pdc also measures overload. I suspect I have some bad wires somewhere. No power to pin 7 on injection pump harness but good ground. Completely lost and thinking of just replacing engine wiring harness. Tried a spare ecm also that I known works great. Anyone have any ideas before I do that?

Extremely helpful write up! Very well done! Just have a couple questions. The thick wire that runs from alternator to PDC is completely removed and replaced with a wire from alternator to positive battery terminal on passenger side battery correct? And then the wire that you had made up with the clip in the middle goes from ground terminal on driver side battery to where? Does it go to PDC or do I ground it the same place as the 4 other grounds that were exposed during this process? If does go to the other 4 grounds then do I have to also run a wire from negative termial on battery to PDC?