Have a 03 extended cab 4x4 5.4 motor that intermittently has electrical issues when the key is not in the ignition. Dash trouble lights have turned on, headlights (bright) Dim lights are not working at all. Radio turns on with no key in ignition after sitting by itself nobody in it and being off a while. My initial thought was the gem module. After taking it off the GEM shows no signs of water anywhere. The fuse box does however can this even cause that? I can see it shorting something or not working but turning on things without key in the ignition?

The dim headlights not working I do have power to one of the wires on the back of headlight when on dim so even though bulbs look fine gonna pick them up.

Any suggestions or anyone with something similar that has happened to them and your solution that fixed it? gonna order a fuse box since it has signs of water getting to it. Just not sure that will even fix the problem?!