Where is the fuel pump relay located on a 2004 ford expediton.

67sunbeam, this is a rather complex system. The actual fuel pump,relay is located in the central conjunction box which is located behind the left kick panel. IT IS NON SERVACEABLE according to Ford. There is an inertia switch inside the left rear cab corner near the bottom. Just push it into the relay, if it was tripped, it will click.There is a fuseable link in the engine compartment next to the battery on the engine side. Aside from that, the fuel pump it self could have connection problems and more. Beyond the simple things, unless you fix cars for a living, it may cost you more to fix it you self than to bring it to a pro.

I know this an old post but, there is a known issue on these. The circuit board within the fuse box is faulty. Getting the repaired is in only a temporary fix, unfortunately the only true fix is to replace with the updated circuit board in the newer numbered fuse boxes. I’ve done a stand alone relay out of the fuse box, replaced the relay on the board and the same issues kept occurring every 6 months or so. The last time it happened it actually got so hot it burned the circuit board itself. Replaced it with the updated one and boom no more issues. I know it’s expensive to replace but the added cost of burning up a fuel pump and/ or the fire hazard it is worth the money.

The fuel pump relay is soldered on the circuit board inside the fuse box. There is a great step by step guide here. http://www.sparkys-answers.com/2011/03/2003-ford-expedition-no-run-no-fuel.html
I was recently having problems with my wife's 2004 expedition intermittently starting(would crank and turn over but would not stay running) and died once when driving. I would go to restart about an hour later and truck would start fine. Rinse and Repeat. I had the truck towed twice to a mechanic who admitted that intermittent problems are the worst but did not think it was the fuel pump. So I did some research on the internet and found Sparky's post about relay which made sense in our case. I took board apart and bought replacement part from digikey for about 4 dollars and being a relative novice found a local cell phone repair shop that de-soldered old relay(middle of the five relays is fuel pump relay) and soldered in new one for 30 dollars and avoided buying a whole new fuse box assembly. Hope this helps someone as sparky's post helped me.