Mystery connector in truck bed

There is a white 4-pin connector near the rear upper driver-side corner of the truck bed. It is similar to a flat 4-pin trailer light connector.


The wires join a factory wiring harness connecting to the tail lights.

The red wire with the white stripe, on the right, is connected to the brake lights. The solid red wire, on the left side, is not connected to anything. (It was just tucked up into the frame under the bed.)

Does anyone know what this is for? What are the two black wires in the center connected too?

 

Camper shell third brake light wiring?

 

was added by previous owner ?? perhaps high mount stop light for a cap??

 

maybe someone had a cap on the truck and its for 3rd brake light on cap so maybe one is also a ground, also one might be a hot wire for interior lights in cap.i have 3 wires on my cap, one is brake, one is ground, and one is hot wire for interior light inside cap.

 

This is the hook up for lighting in a truck cap (I'm guessing a prior owner had installed). It's identical to the one on my truck that provides power to the third brake light at the top of the rear window and interior light on my Leer. I don't remember offhand which wires are which but one will be brake circuit and the cap-dome can be wired to have available power anytime or only when the running lights are on (this will save your battery if you forget and leave a cap dome light on all day).

 

Damn. When I read the title I thought I was going to discover something new about my own truck! But yeah, I have something similar for the brake light on my shell, so I will have to agree with the previous posts on that.

 

when I bought a Leer Cap, the Leer dealer installed the same wiring for the break and interior light.