Since my backprobe wire is part of a fused jumper wire, I connected battery voltage to the circuit and started the vehicle. I placed a jumper wire into the cavity to backprobe the circuit, no volts. The wiring diagrams stated that the fuel pump relay output wire was dark green/yellow and it was located in cavity 3 of connector C270K. My next test would involve locating the output circuit from the relay. I did some reading and found that there are five internal, non serviceable relays inside the fuse block. Since my wiring diagrams stated the relay was located in the fuse box, but did not give a specific position, I looked in the owners manual for more info. There is a black plastic cover that has to be pulled off of the actual fuse box. Pull the edge loose at the firewall end and pivot the cover back. There are a couple of covers that have to be removed. I decided to go to the interior fuse box, where my wiring diagrams, stated the fuel pump relay and fuse are located. A quick check found no fuel pressure and a code P0231 (low voltage on fuel pump monitor circuit). This 2003 Ford Expedition came in with a no run condition.

2005 expedition fuel pump circuit