Adding a 7-Way and Trailer Brake Controller to a 2017 Subaru Outback with Factory Trailer Connector

Updated 07/31/2017 | Published 07/28/2017

Products Featured in This Question

Curt Custom Wiring Adapter for Trailer Brake Controllers - Dual Plug In

(37)

$20.01

Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires

(3544)

$118.67

Question:

I have a 2017 Subaru Outback with a factory installed Subaru hitch with a harness wiring that can engage all my trailer lights brake, running lights and signal lights. However this wiring does not engage the trailer brakes. Is there a custom wiring adaptor for a trailer brake controller that can be used with the existing wiring so that a whole new wiring system does not need to be installed for a brake controller.

asked by: Ricardo R

Expert Reply:

You can add a brake controller to your 2017 Subaru Outback but there isn't a plug-in harness to do so. To activate the trailer brakes your Outback and trailer will need to have 7-Way trailer connectors.

On the vehicle side you are only doing some hardwiring and you will use the existing 4-Way connector on the vehicle to do some of the installation. What you will need on the vehicle side is installation kit # ETBC7 and a brake controller. I recommend the P2 # 90885 because it is easy to set up and use and it is reliable. I have included some links that show and explain the ETBC7 installation for you.

On the trailer side you will need a 7-Way such as # H20046. On this harness white is ground, red is left turn/brake, brown is right turn/brake, green is tail lights, blue is for the electric brakes, black is 12 volt power, and yellow is aux power or reverse lights. Always wire by function and not color since there technically isn't a standard for trailers.

expert reply by: Michael H