I've lost my left turn and brake light, on my 7 prong plug on the truck. Went to plug in a trailer and fiddled around, checked the current and I'm not getting any left turn/brake at the plug. All others work fine on truck, and trailer.

Is there a separate fuse for this circuit? If so, any ideas where it's located.

Thank you

Rich in Democratland (TEMPORARILY)

there is a separate fuse for this under the hood

On an 05, that fuse is not under the hood. The trailer fuse is right next to the truck fuse in the fuse panel in the driver side of the dash.

I think my 06 is under the hood, I borrowed a small lawn mower type trailer from a friend and it blew every fuse there was.