Back in July, I had to lift my bed to replace the fuel pump. After we got it all fixed up and got the bed back on. I noticed a wiring harness hanging a bit. I asked my stepson what it went to, as he was the man under the truck. He said he had no idea. Everything was hooked back up and I know it is because I just passed an inspection about a month ago. He said it was just there when he went under the truck to unbolt the bed. Not sure how great the pic is. Its got 2 rows of connectors, Looks like 8 flat ones and 2 "L" shaped. Its at the very back of the truck. I hooked it into the safety chain loop on my Reese hitch. What the heck is this? My thinking is its a connector for trailer lights. Am I correct?

 

factory 7 way connector. plugs into the back of the 7 way round trailer plug.