What is this blank connector duct taped under the dash (near OBD port). 2013 F-150.

 

I think that's for the trailer brake controller

 

I will confirm that. Just installed one today!

 

Hmm...I have a factory installed trailer brake controller & am the original owner of the truck....is it an extra or how does it get used?

 

If it came factory, then it should be functional. Use the 7 pin harness with a trailer that has electronic brakes. Then you need to adjust the controller to apply the proper amount of brake to the trailer. I imagine its different for every trailer.

 

I was under the dash on my 2012 last week and noticed the same plug. I think mine was blank also, but I will check this evening. I also have the factory TBC and it's fully functional.

 

If your truck comes WITHOUT the brake controller, the end of the harness is plugged into that. Mine was.

 

It is highly likely that it is indeed for an aftermarket brake controller. Most vehicles now have "standard" wiring harnesses that include every plug required even for options that don't end up on the vehicle. It's more cost effective for a single harness to be used, rather than having a dozen or more harnesses that you have to sequence into the assembly line.

I know we once produced a 34 pin connector that only had 2 pins installed for certain applications. I shook my head, but in hindsight it kind of made sense. Line worker just plugs the same connector into the same spot on the vehicle every single time.

 

I have seen the same under the pass seat in my XLT. There are several wires for the heated seats. Connector is the same but wires are not there. Same for the inverter option. The circuit runs from the underhood fusebox (fuse is also installed) but ends at the connector near the ebrake.
The connector pictures is just taped to the harness to have a place for the brake connector to live. Probably makes it easier to install the harness because it is not hanging out getting caught on things.