Help identifying plug behind dash (under fuse block)

I have a small white plug with four wires in it (red/blue/grey/brown). Couldn't get a good picture because it's taped to the harness, it's right behind the coin tray. I have a 2012 base model, 4cyl automatic. I have no idea what it's for in other optioned trucks. Looking online now for a connector location diagram.

 

should be to plug in an electric trailer brake controller

 

That was my 1st thought, but the color and number of wires are wrong. Besides that, I'm pretty sure a 4 cyl auto wouldn't come prewired for a trailer brake controller.
http://www.customtacos.com/tech.old...toyewd/06toypdf/ewd/2006/tacoma/h/em01d40.pdf

 

You're going to get zero help until you post a pic.

 

Try this:
Cable routing:
https://www.customtacos.com/tech.ol...oyewd/06toypdf/ewd/2006/tacoma/g/em01d0up.pdf

 

I'll get a picture later today.

 

The wire is only about 2" long where it exits the harness so it has to plug into something close.

 

I believe I found out which plug it is.
It's "IR1", Trailer Towing EWD (electrical wiring diagram for a 2015, is where I found it).

 

Red - Left turn
Brown - Right turn
Blue - Stop light
Grey - Battery + (30A Towing fuse)