Recommended 4-Way and 7-Way Wiring Harness for a 2019 Lexus RX 350L Using a Curt Echo

Question:

My vehicle is a 2019 RX350L. I would like to buy/install a 4-7 pin socket and use your bluetooth brake controller on this vehicle. My RX350L does have the tow prep package installed from the factory. I would also like to ask if you know the location of my vehicle tow harness? My Lexus dealer service department has no idea. Thank you

asked by: Julian R

Expert Reply:

To add a 4-way and 7-way connector to your 2019 Lexus RX 350L you are going to need two separate wiring harnesses as there isn't one available that can do both. There are no custom fit 7-way harnesses either so this is by far the best and only option.

The first harness you will need is the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package item # 56083. The custom-fit T-connector plugs into your Lexus's factory tow package wiring harness, which is located behind the rear bumper, along the driver's-side frame rail.

The second harness you will need is the Universal Installation Kit for Trailer Brake Controller item # ETBC7L. The kit includes a pre-wired 7- and 4-way trailer connector that mounts easily at the rear of your Lexus with an included bracket. This kit is designed for use on a vehicle with an existing 4-way flat trailer connector and plugs directly into it.

You will then connect the black wire to the positive post on your RX 350L's battery, the white wire to ground, and the yellow wire to your vehicle's reverse circuit if applicable. This will provide you with the ability to control your trailer's brakes and also provide you with a 12v power wire for you trailer's accessory lights.

Since you are using the Curt Echo Brake Controller item # C51180 you won't need the brake controller wire that runs from the hitch to your cab. If you change your mind on brake controllers and go with a traditional in cab option you will want the item # ETBC7 which has the blue brake controller wire.

I have linked some installation videos below so you can see how to get these parts set up.

I saw you were looking at the Curt Trailer item # C13394. This hitch is custom fit for your 2019 Lexus RX 350L. It fits all models except for the ones with dual exhaust.

To round out your towing setup I recommend the Curt Towing Starter Kit for 2" Hitches item # C45534. This towing kit will provide you with a 2" ball and a fixed ball mount with a 3/4" rise and 2" drop. It also includes a hitch pin and clip, hitch receiver lock with keys, hitch cover, and a storage case.