Availability of Vehicle 4-Way to Trailer 7-Way Adapter

Question

Question:

I have a car with a 4 pin connector and and RV with a 7 pin connector. Do you have an adapter that I could use to connect my cars 4 pin to my RVs 7 pin? Thank you for any help.

asked by: Joann

0

Expert Reply:

Hey Joann! You can use the Hopkins Plug-In Trailer Connector Adapter - 4-Way Flat to 7-Blade # HM54RV. This will carry the light functions from your vehicles 4-way over to the trailer. Does your trailer have brakes? Keep in mind, this will not allow you to use trailer brakes. If you need to use the brakes then you want to upgrade to a complete 7-way using the # ETBC7 along with a brake controller like # RED52VR.

expert reply by: Robin H

0

Hopkins 4-way to 7-way Adapter
(click to enlarge)

Robin H.

9/2/2025

Hey Joann, did the Hopkins adapter work for your setup, or did you decide to upgrade to a complete 7-way with a brake controller? I'm curious to know how it turned out, as it could help others with similar needs.

Joann

9/2/2025

@RobinH I didn’t purchase the Hopkins adapter yet. I am looking at the Autowbrake electronic brake controller for the pop up camping trailer I want to purchase and tow with my car. The trailer has a 7 pin connection and my car has a 4 pin. I want to use the Autowbrake controller so that I can use the electric brakes on the trailer even though my car has a 4 pin connection. Everything I read about the wiring of this brake controller to the junction box of the trailer would allow the electric brakes to become engaged following the instructions on the manufacturer’s web site. I would also need the Hopkins adapter to connect my car’s 4 pin harness to the trailer’s 7 pin harness.

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