Well I talked to the shop today, they think they figured out where the problem lies.

They said there is a short behind the fuse panel in the cab...this would make sense since the fuses look good but it's still not working.

I also had an issue where the front windshield washer was not pumping fluid and the rear wiper / washer is completely unresponsive....again the fuses appear ok, so this makes since, it's probably all related!

Hopefully they have it straightened out Monday and I can pick it up w/o too much labor needed to fix the issue. (fingers crossed!)

 

Well, if the issue persists, here's my $.02...

Had opposite problem where highbeams latched on and would not turn off unless all lamps switched off. Found 4VDC was always present at highbeam relay coil and it could not de-energize to 0VDC.

Pull factory fog lamp relay then check lamps. If fail then swap headlamp/highbeam relay with similar relay in PDC then check lamps. Good Luck.