Need 7-Way Trailer Connector for 2013 Subaru Outback for Use with Trailer Brake Controller

Expert Reply:

In order to wire a 7-way trailer connector for use with a brake controller you will first need to have a working 4-pole trailer connector on your vehicle. We do offer custom plug-and-play 4-pole converter harnesses for your Outback wagon, both powered and non-powered types.

If your trailer has only basic lighting and you do not intend to add any additional lights to it, then you can use non-powered converter # 118467 which is shown in the linked video. This plugs in to your R79 connector to provide a 4-pole trailer connector. If you have a lot of lights on the trailer, intend to add any in the future, or if you will be towing other trailers as well, then you might instead prefer a powered converter with a higher current capacity such as # C56040 from Curt. This harness uses a separate 12V power feed (included in the R79 connector) to draw power for the trailer lights from the battery, rather than through the vehicle tail light wiring. A video is included for this item as well. Written instructions are provided for both harnesses.

Once you have installed either of these 4-pole harnesses you will then need to install our electric trailer brake control kit, # ETBC7. This kit includes the 7-way connector, bracket, and wiring components you will need to complete the trailer brake controller installation. I have linked an article describing installation of this kit in a Subaru Outback Wagon.

You will connect your 4-pole to the matching plug on the 7-way and then complete the wiring connections for the 12V trailer auxiliary power wire and reverse lights (if desired) and for the blue wire that carries the output signal from the brake controller. The remainder of the wiring connections will be made in the passenger compartment to provide 12V power and a brake input signal to the brake controller, and to connect its output signal for the trailer brakes to the 7-way connector. Everything you need is included in the ETBC7 kit.

If you do not already own your brake controller you might want to review the linked article that reviews the different types and their relative benefits. We usually suggest proportional controllers over the time-delay type; the Tekonsha PowerTrac # 39523 that you referenced is a time-delay unit. I have also included an article concerning brake controller installations.

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