Having an issue with my trailer lights...using 7-pin connector. 2011 XLT

When I plug the trailer in...the only lights I get power to are my left turn signals. No power to anything else. I verified this by checking the truck end of the plug, and the only time I got power to ANY of the pins was when the left turn signal was on.

I plugged the trailer into my buddies truck.....all lights worked flawlessly. So it's not the trailer.

I checked and swapped all the fuses and relays I could find in the engine bay fuse box.

Any ideas?