How To Connect a 4-Way Flat on 2012 Toyota Highlander To 5-Way Flat on LoadRite Trailer

Question:

My 2012 Toyota Highlander came with a 4 pin trailer hitch electrical connector. Unfortunately, my LoadRite trailer has a 5 pin flat connector. I believe the 5th pin is used somehow in conjunction with the trailers surge brake. What are the consequences of not using the 5th pin and/or how do I correctly connect the 5th pin to my SUV?

asked by: Gary S

Expert Reply:

You are correct that the extra pin on the 5-Way flat connector is used to deactivate the trailers surge brake when going in reverse. The 5-Way flat is used for trailers with surge brakes. The additional wire is tapped into the backup lights to disengage the hydraulic trailer coupler (actuator) when the vehicle is reversing, thus turning off the trailer brakes.

I would recommend to connect the extra wire on the 5-Way so your towing system is working properly. If not attached, the trailers brakes would lock up when going in reverse.

There is an easy solution for you to connect the 4-Way on your 2012 Toyota Highlander to the 5-Way on your LoadRite trailer. You can use the Tow Ready 4-Way to 5-Way Adapter, part # 20036. This adapter will plug into your existing 4-Way on your vehicle and the extra blue wire is spliced into the reverse light wire on your vehicle.

The wire you are going to be looking for to activate the reverse lockout feature for your surge brakes will be the wire that powers the reverse light bulbs.

I would recommend using a circuit tester like part # PTW2993, to determine which wire has power when the reverse lights are illuminated and no voltage when the lights are not activated. I am including a review video for the # 20036 that shows exactly how it's done.