I have a 2013 Ford F-150 that every so often will not start and has no power to the dash. I cleaned all the terminals and checked the fuses but still nothing. I put another vehicle to oust it and still has no power but the dash now flashes and won’t start. Then I wiggle the fuse box and the lights inside and dash come o. It starts and stays running.

 

I would remove and inspect the fuse box. Hopefully it is just the fuse box and not the harness.

 

Need to do more real testing.

These trucks were common to have issues with the fuel pump fuse on the box. Guess it's not much of a stretch to have other fuse/box issues