Hemi won't fire
I have a 5.7 engine 545 RFE transmission and computer from an 05 truck
I modified the harness myself.
I'm not sure if any of this is helpful, but here is how I wired mine.
I added a relay to power all the run/start functions of the computer using a 12 gauge circuit and 30 amp fuse. This circuit is then split through fuses and smaller wires to power the PCM, brake switch, fuel pump relay, and backup lamps.
The PCM and the relay control input to the fuel pump relay are both powered through this relay in the run and start positions.
The PCM grounds the ASD relay control through a wire from the PCM.
The PCM grounds the Fuel Pump relay control through a wire from the PCM.
I modified the truck fuel pump and my tank to make them work together so fuel pressure is regulated through the pump.
It would not start initially because my injectors were plugged so it was not getting any fuel. Once I cleaned the injectors It fired right off.
I did testing with the pump sitting in a 5 gallon bucket. The truck fuel rail should have a port for pressure testing on the passenger side. I know mine does.
My troubleshooting recommendation is to check for ground from the PCM to the fuel pump relay and ASD relays in the start and run positions.