Recommended Brake Controller to Replace the Factory Controller on a 2010 GMC Sierra 2500

Updated 03/02/2025 | Published 02/25/2025

Products Featured in This Question

Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional

(6643)

$155.79

12 Gauge Wire - Black Primary - Per Foot

(30)

$2.01

Question:

I have 2010 GMC 2500 Sierra with a factory trailer brake system thats not working again.. ? Can I buy a brake controller and not use the factory controller? If so is there wiring instuctions on how to?

asked by: Mark A

Expert Reply:

Yes, you can Mark! I recommend the Tekonsha Prodigy P3 Trailer Brake Controller item # 90195. This is a proportional brake controller that automatically adjusts your trailer's braking based on the deceleration of your Sierra.

Since your Sierra has the factory installed integrated trailer brake controller (ITBC), the tow package wiring that exists under the dash can be used to install an aftermarket controller. The wiring is located under the dash, above where the driver's left knee would be. You'll be looking for a wiring harness with a white tag on it.

The red/black tow package wire connects to the black controller wire
The white tow package wire connects to the white brake controller wire
The light blue tow package wire connects to the red brake controller wire.
The orange tow package wire is NOT needed, cap off the end and bundle the wire up out of the way.

The dark blue tow package wire is not going to be used. Instead, take the dark blue brake controller wire exiting the rear of the controller and extend it with a length of 12 gauge wire item # 12-1-1 and run it through the firewall and under your truck to the rear bumper. Behind the 7-way trailer connector at the rear bumper, remove the wire loom from the wiring harness that feeds the 7-way connector behind the rear bumper. Locate the blue wire, and sever it about 6" behind the connector. Take the wire that you ran from the brake controller, and attach it to the blue wire that attaches to the trailer connector. The remaining portion of the factory installed blue wire should be capped off and taped up out of the way so it cannot short out on anything under the vehicle.

There will be two connections that need to be made under the hood. The power feed wire for the aftermarket brake controller is located between the under hood fuse box and the fender. Look for a wire with a large ring terminal on the end of it. The 12-volt accessory power feed to the trailer connector will also need to be connected, if it has not been already. This wire is located under the brake booster, and also has a ring terminal on it. These wires will connect to the power studs located on the forward side of the fuse box.

I have attached a photo below that shows the locations of the wires and the power studs.