97 f250 taillights

I am having a problem with the right side singnal-brake light on my 97 f250 2wd I am not getting any voltage to the back for the right side brake-signal light. It started last october so I replaced the multifunction switch and that solved the problem, but this time a new switch did not help any ideas???

Trace the harness back from the tail light and there should be a connector near the back of the truck (I can't remember just where) that you can pull apart and check for 12V there. If you have a trailer light connector, check there first.

I found that connector and there is no voltage.Are there anymore connections inside the frame rails?

If you got the truck used, you might want to check for trailer connectors that have been spliced into the harness. I get one in like that now and then where somebody with a fifth wheel has cut and spliced into the harness over the axle and used wire nuts, rather than use the modular connector. The wires sometimes corrode inside the wire nuts and lose contact. Just a thought, cause those can be a real head scratcher and hard to find sometimes. If not, start at the multifunction switch harness and check for power there. ALSO check your fuses, #1 and 23 i believe.

Edit: The left turn wire at the multifunction switch harness connector should be> lt grn/org: right>org/lt blu