I started at the fuel pump testing the system all the way to the Auto Choke/Shut off Relay. I took a paper clip and bridged the hot wires together. The pump worked and the truck started. I then proceeded to replace the relay hoping that it would fix my problem and it didn't. Now I am trying to figure out what is causing the relay to shut down the fuel pump and how to fix it. I have a 2004.5 with a 5.9 that has been recently rebuilt. The fuel system has been modified with the Air Dog lift pump and water separator system, so I know that their is not any water in the fuel potently causing a censor to go off. Does anyone know what I need to do or where I can find some literature to help me?

 

I would say that its in the relay control circuit wiring or the ECM, since you were able to power the pump by jumping the relay with the paperclip. Do you have any other things not working like warning lights that don't come on when you turn the key?

 

If you bump the key without starting the engine you should get about 25 seconds of fuel pump operation. but if you just turn on the key it will only be about 2 seconds of FP operation.

Here a a couple schematics

2004 Dodge fuel pump control circuit.pdf

2004 Dodge fuel pump control circuit 2.pdf

 

The schematics are very helpful. Thank you for sharing that. All indicator lights appear to be working, so I'm leaning to a broken wire some where.

 

Some of the schematics are pretty generic for diesel or gas vehicles. I did notice that the 2005 schematics don't show a lift pump wired to the ECM the same way as the 2004 so there is some chance that yours may go either way.

2005 dodge fuel system.pdf

2005 schematics:

engine-controls-1-of-4 2005 Dodge.pdf

engine-controls-2-of-4 2005 Dodge.pdf

engine-controls-3-of-4 2005 Dodge.pdf

engine-controls-4-of-4 Dodge 2005.pdf