Durial

Same problem going on with 2 of my trucks (an 01 and 02) had to buy another (2000) cummins to continue working, getting desperate and waiting money now I'm sitting on 2 ecms and 2 pcms and 2 vp44s (1 new each and 1 known good each) for this no start issues, then after reading this forum got both trucks to start with unplugging either c1 or c3 from pcm If both are plugged in it doesnt start or instantly dies if plugged in while running Was also wondering if yall found the exact reasoning/fix for this would be very appreciative , just need to know what to do On a side note on my wrecked 01 I was able to mix and match all 3 new and old ecm and pcms and it started and ran, same with 4 differant vp44s, through lots of trial and error they are at least known good