Wiring a Camper Shell Third Brake Light on a 2011 Chevy Silverado

Updated 07/08/2025 | Published 01/14/2015

Question:

How can I connect a 3rd light on a contractors cap on a 2011 chevy silverado?It has a factory installed 7pin harness. But the directional and the brakes use a single filament bulb.

asked by: John

Expert Reply:

Like you said, most trailers in the US have what is called a 2-wire or combined system with the turn signals and brake lights on the same circuit. You would not tap into the tow package wiring if you need just a brake light signal.

There is a dedicated brake light only wire located up under the dash and to the left of the steering column. It is with a wire bundle held together with a white tag. There should be an orange wire that is the center high mount stop lamp wire (CHMSL) that you could use.

You would need to attach wire to the end of it, route it through the firewall, under the truck, and over to where it needs to go.

It is also possible that the truck has a wire under the bed somewhere for this purpose. A place that sells and installs camper shells might be able to tell you where the wire might be.

expert reply by: Michael H

Vinnie

7/8/2025

After a skeptical look up under the dash, I found three extra wires just hanging out right next to the left of the steering column. At first, I was surprised, but then saw there was no tag, just electrical tape around the ends. So, I tested the orange wire anyway and sure enough with the push of the peddle I could see the red LED's light up in the reflection of my patio door. Presto Poofo the rest is history. Thanks Michael!