1998 Tahoe Electrical Problem

How often does it blow? Do you notice it blowing when braking only? Do you have a trailer light harness attached? I'm looking at a wiring diagram. It's a typical or generic diagram for 1988-1998 Chevy trucks. Is it fuse #1? If not, what fuse number is it. Does it happen after it rains? What did the mechanic/dealer replace or do to try and fix the problem? Any more info would help. I would start by checking the wire harness connector going to the rear lights. Follow the wires behind where the bumper is and there should be a connector p in the corner of the drivers side rear fender. Check it for damage from water, etc. More info would help.