2xRustler

I would take it back to the dealer who put it on. I actually told the dealer if they put one on they would have to discount the price  of the vehicle. I'll gladly advertise with a frame, but don't put stickers on my paint. 
They likely remove other stickers so they have plastic razor blades and paint safe solvents. I worked at an RV dealer long ago and we did this. This also puts the liability for any paint damage on them

My 2014 has 44k on it. Same thing, noticed it shortly after i bought it with 27k on it. The R/T I just drove last week while I was getting the ABS recall taken care of had 1105 miles on it and made the exact same noise. Right or wrong, it's something these vehicles do. 

It worked out just fine. The kayaks on the roof created a crazy amount of drag and it was windy. Averaged 16.8 MPG 

Yeah, it is weird but it's fixed. we'll see if it lasts while towing tomorrow

The converter is in fact bad. I wired in a new one and everything works as it should. It appears that sometimes the internal wiring will go bad and send all power to one bulb. The fuse won't blow because there is only the draw from one bulb which is not enough to overload the circuit. 

All is well with the car when I unplug the harness. I ordered a converter that I will wire in this weekend. I'm curious what fried the first one

same thing.. The right rear light lights up and nothing else works.

No relays, there is a fuse on the power wire. The harness has the connectors for the the tail lights and turn signals to piggyback onto the signals from those circuits. There is a little black box (converter) that is powered by the power wire and converts the separate turn and tail lights (5 wires) into 4 wires for the trailer, and supplies power for the trailer lights. It appears that the converter is malfunctioning and sending all the power to the right turn signal circuit. `

I have a 2014 SXT with LED Tail lights. I installed a Curt hitch and wire harness last summer. Everything worked fine. I mostly use the hitch for a basket or other accessories. The harness worked fine when I towed with it this spring.
I got home this afternoon in my Focus and noticed the right rear turn signal bulb was lit on the DJ. The DJ had not been touched today. I got in the DJ and turned on the flashers, The light never went out but got brighter when it blinked. I took the tail light assembly off because I was going to pull the bulb. I decided to disconnect the T-connector and plug the factory harness into the bulb. After this, the light acted normally. The problem has to be in the T-connector and/or converter which is all one unit. The fuse is not blown and all connections seem to be ok. I have not had any to dig further. Does anyone have any suggestions about where to start?

Our 2014 SXT was originally owned by Enterprise