Converting 4-Way Trailer Connector to 7-Way on 2009 Toyota Highlander

Updated 05/18/2019 | Published 05/17/2019

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(1124)

$45.90

Adapter 4-Pole to 7-Pole and 4-Pole

(659)

$61.64

Curt Echo Wireless Brake Controller - 7-Way Plug-in w/ Bluetooth App - Up to 2 Axles - Proportional

(1769)

$279.95

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

(3398)

$121.17

7-Way RV Upgrade Kit for Trailer Brake Controller Installation - 12 Gauge Wires

(337)

$96.74

Tekonsha Primus IQ Trailer Brake Controller - Up to 3 Axles - Proportional

(2158)

$90.04

Question:

I have an 09 Toyota highlander that I recently installed Part#C56217 to make it tow ready. I bought a Sun Tracker tandem trailer with brakes with a 7 round connection. The trailer has brakes, so I do not need to install brake controller in the vehicle. My question is which parts do I need to convert and could you provide install instructions or diagram in order to assist with the install. Thanks.

asked by: Brandon S

Expert Reply:

Since you already have the Curt # C56217 4-way connector installed you just need to convert it to a 7-way. If you want a fully functioning 7-way the easiest way is with our # ETBC7 kit. I've linked a video that shows an install on a 2010 Highlander for you. The process is the same as on your 2009.

You said you don't need a brake controller installed because the trailer has brakes. If those brakes are electric then a brake controller is exactly what you do need in order to power those brakes. Without a controller there's nothing to trigger the trailer brakes. If they're hydraulic brakes then you don't need a brake controller in the Highlander. If this is the case then you don't need the # ETBC7 kit and instead can just use an adapter with no wiring like part # 37185. I linked a video of this install as well. If you only need the trailer's lights to function then really you just plug it in to the 4-way you have, ground the white wire to the Highlander's frame and mount it.

Another option is a 7-way that has all the functions working except for the trailer brakes. This is actually what I recommend for you. Use part # ETBC7L which is just like the # ETBC7 kit except there's no wire for the electric brakes to be installed which is the most difficult step. If your trailer's brakes aren't electric then this is all you need anyway. Additionally, if your trailer does have electric brakes and you do need a brake controller you can use this kit and then get the Curt Echo, part # C51180, because it doesn't install inside the Highlander and doesn't need the brake circuit to be active. Instead if plugs into the new 7-way at the back of the vehicle and uses just the 12 volt circuit for power and engages the trailer's brakes based on the inertia of the Highlander slowing down.

If you do need a brake controller and prefer a more traditional style than the Echo then you'll need to install the complete # ETBC7 kit. In this case I recommend the Primus IQ, part # TK90160, for a more economical yet quality brake controller.