cranks but won't start?

Whataya want me to do? Come down there and do it for you? LOL Just kidding!

I'm not sure which year/model you are dealing with. On mine, there is a white and black connector where some of the wires connect inside the fuse panel. You may need to look at the wiring diagram for yours and see where there is a ground on the PCM going to the PDC. That should be the isolated ground connection. I'm not sure where the isolated ground actually is connected to the system ground.

On these new wiring diagrams, the ground connections are shown separately from the positive sections. I have to stop and remind myself of this. Let me look at my diagram and I will see if I can find the ground pin-out on the PCM. I'll go back and see which year model you have.