I'm confused I am try to figure out where my communication problem .I have done the tests that i got from here and when I do the check to ground on the white and black wires my gauge does not move at all. I was looking around online and I saw pretty much the same test but the color of the wires it said to check on post 1 and 2 on the FPCM are totally different. My wires are one white and one black and they are together in a shielded cable in the wiring harness with the others for the FPCM is this correct? I have a 2001 2500 quad cab long bed 2wd with auto transmission.I have replaced the lift pump and the VP44 it will crank but NO START. 

Thanks in advance for any HELP my truck has been down for over a month!!

Basically, it ohm test from pin to pin from the VP44 plug to the ECM plug. The ohm value should be below 5 ohms for all. Now as for pin to ground with both plug unhooked yet you should get infinite ohms in other words, no shorts to ground. Beyond that, I would do the BlueChip hot wire test and see if the VP44 will fire up as a standalone. 

 

https://www.bluechipdiesel.com/

 

Thanks for the information I will try this and I think I'm going to change up the ground wire situation as I have recently read on here.

Thanks Shaun