How to Install a Trailer Brake Controller on a 2009 Chevy Silverado

Updated 05/04/2026 | Published 04/22/2014

Question:

which wire plug do i need for 2009 chevy truck from the brake controller to under dash

asked by: Tim

Expert Reply:

On the 2009 Chevy Silverado there is no port to plug in a brake controller. Instead GM put a tow package wire bundle under the dash. You would use the harness with the blunt cut wires that comes with the brake controller and splice into the tow package wires.

The wire bundle is located under the dash, to the left of the steering column, held together with a white tag.

The wire functions as as follows:

Truck red/black to brake controller black for 12 volt power
Truck white to controller white for ground
Truck light blue/white to controller red for brake light signal
Truck dark blue to controller blue for out to trailer brakes
Truck orange is not used

I have included a link to a help article that explains installing a brake controller on a 2009 Silverado. There may also be some connections that need to be made under the hood.

For a brake controller I recommend the P2, # 90885 because it is easy to set up, easy to use, and its reliable.

expert reply by: Michael H

Scott S.

2/16/2025

My 2009 Silverado doesn't have the wire bundle for the trailer brake controller is there a port for it

Kate F.

2/17/2025

@ScottS Hello Scott, I am going to turn this into it's own question so I can attach an image.. Please look out for second email.

Thyrus P.

5/2/2026

I bought a brake controller for my 08 avalanche but it has a 8pin connection. What wire harness will work for me

Jerred H.

5/4/2026

@ThyrusP That depends on what brand and model brake controller you purchased and I do not see an order number so I can't tell you which one you need. There are no custom fit adapters for your Avalanche because GM did not install a brake controller port in them. You'll need to use a universal wiring harness that matches the brand of your brake controller.