What is the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036 Used For

Question:

What is the wire for? I know it hooks to reverse lights but what is the purpose of the wire?

asked by: Wesley

Expert Reply:

Typically the Tow Ready 4 Pole to 5 Pole Trailer Wiring Adapter # 20036 is used to activate a Solenoid Valve like part # T4748800 on a surge brake actuator.

Surge actuators activate the brakes on a trailer when the weight of the trailer is still moving forward while the coupler is slowing down. That compression is what causes the master cylinder to activate your trailer brakes.

If you back up with a trailer that is using a surge brake actuator you will be causing that compression to take place since the trailer will need to be pushed. This will activate your trailer brakes to activate and make it very difficult to back your trailer up. Some surge brake actuators have solenoid valve like what I mentioned above which lets the surge actuator know that you are backing up and not coming to a stop. It then "locks out" the actuator so that it does not cause the trailer brakes to activate.

expert reply by: Jon G

Peter

5/31/2020

I have a short haul, on fairly flat road. I have a five prong trailer with brake assistance. What are the risks if I don’t install the 4 to 5 adaptor?

Chris R.

6/3/2020

All the light functions on the trailer will still work, you just won't be able to activate the reverse lockout solenoid. This is what prevents the brakes from locking up when backing up the trailer - otherwise the brakes will work like normal during travel.