This is on my 4/99 build F250 CC 4wd. What's there as far as wiring for trailers I assume is all factory installed. It came with a hitch and a flat 4 wire plug. I needed to install a brake controller which I did easily and found the plug up under the dash. Head to the back for a 7 way install and I find 7 wires in a bundle, each labeled by ford it appears, with a small bit of heat shrink on each wires end. land those wires on my 7 way plug and find I have no brake controller power until a 30 amp maxi fuse is installed under hood for that, Ok I'll get one today. But... I still have no power to the back up light pin nor the aux 12V power pin. Thoughts???

 

I found in my owners manual there is also a 30 amp maxi for the 12V trailer power. Still no back ups and the fuse is good. Ah well.

 

Kick around this site. There are a lot of tips and discussions on troubleshooting.
https://www.etrailer.com/t1-2021_Ford_F-150.htm

 

Did you check to see if the trailer backup lamp relay is installed? If installed, does it "click" when the ignition switch is in RUN .and. the shift lever is in REV?

 

That bit of info I did not see in the manual. It would explain why I have no BU's. I will look today and see what, what. Thank you.