Hey, hoping to get a little help, I have a 2004 5.4l F250, fuel pump stopped running, inertia switch good, integrated fuel pump relay is CJB not turning on. I wire in the by pass relay. Still doesn’t work. If I jumper the coil ground to ground on truck my added relay works fine. My PCM appears to not be grounding the relay coil. I tested my wire for continuity from PCM connector till my relay. Wire is good, not broken. So it appears my problem is in the PCM. Is there some conditions that have to be met before it will turn on my fuel pump?

any help would be greatly appreciated

i check a bunch of previous forums, couldn’t find anything about PCM part of this problem

 

Does the fuel pump run for a couple of seconds when first turning the ignition switch from OFF to RUN to prime the fuel rail?
If it does the PCM is controlling the fuel pump GND.
The next thing that happens is the PCM needs to sense the engine turning before it will turn the fuel pump back on after START is selected on the ignition switch.
I think it monitors the Crankshaft Position Sensor to see if it is pulsing.