Okay, I've done several searches and I am no closer to finding the problem. I know the default answer is "must be a wiring problem with the trailer" and I am not opposed to that answer, but let me tell you what is going on and what I've tried.

I just got my '06 F-250 PSD with factory TBC a few weeks ago. I have had the trailer for about a year and used it regularly with my old truck ('01 Chevy 2500HD with aftermarket trailer brake) without any problems.

I am about to do a cross country trip with my 20' car hauler so I wanted to do some around-town testing just to make sure there were no hidden tranny problems before I get in the middle of nowhere and find them. So, I hook up the trailer to the truck and the lights work, but the TBC does not see the trailer. I do not get any warnings or errors messages... it is no different than if the trailer wasn't plugged in at all. If I use the manual slide, I simply get the mesage "Trailer Disconnected" which goes away after a few seconds.

Here is what I have done to trouble-shoot:

1. Checked all of the trailer-related fuses
2. Crawled under the trailer and briefly checked wiring
3. Found 3 other brake-equipped trailers and tried hooking them up to my truck. Now, with these I did not connect the tongue, just the wiring.
4. Hooked the trailer back to my old truck, worked fine.

I understand that the Ford TBC is more "sophisticated" than the aftermarket unit that I'm comparing to, and the problem could still be with the trailer. However, that would also mean that the 3 other trailers I tested have faulty wiring too.

I am also using an adapter from the small round pin connector (trailer) to the flat pin (truck). However, I use this same adapter on the old truck without any problems, and the brake control wire is located in the same pin connector on both.

I will add one last tidbit, from my searching I have seen that some people have wires disconnected for their TBC from service work being performed to the engine or tranny. Shortly after I got the truck, it went in for warranty work on the PSD and they did close to $4k worth of warranty work (turbo, egr, etc). Could it be possible that the didn't reconnect something under the hood?

Any help would be appreciated because I leave in just over a week and I really would like the security of the trailer brakes for the long haul.

Thanks,
Adam

P.S. Yes, I did say the old truck was a Chevy. I am really not a Ford OR Chevy guy. However, I will say this.... after having 3 Chevy's, driving an F-250 once it made me wonder why I ever bothered with the Chevys at all. I am truly impressed with the overall fit and finish, as well as the ride of the F-250 compared to my old 2500HD.