This is a real stretch. But have you had the truck in for service lately ? Couple years ago I had my car in for service (I forget for what). When I got is back, I
started blowing the a/c fuse (it also took out my power windows). It was really hot inside.
Anyway, just by accident, I realized that the shop had removed some fuses (or was it relays ?) and put them in backwards. (Far left should have been on far right, and far right should have been on far left). So, I was overly protected on one circuit, and the a/cpower window circuit had too small of a fuse. So, when I switched them back around, everything worked right.