I realized this morning that the upfitter switch on my '10 E350 6.0L Diesel doesn't seem to be working. It controls the fog lights and on-board air and neither power on. I checked the fuse that the manual states controls the switch and that didn't fix it.
Any other simple things to try before I take it my electronics guy?
We have a 2014. Had a loose connection in the upfitter wiring bundle forward of the firewall (located in the top right of the engine compartment). This was causing the switch to fail. It was an easy fix. As noted above, the wiring diagram can be found online. The wire colors were distinct and made it easy to isolate each switch.