Converting a Semi 7-Way Trailer Connector to an RV 7-Way Trailer Connector
Published 10/27/2016 >
Products Featured in This Question
Question:
i am trying to convert my semi 7 way to an rv 7 way trlr
asked by: Shawn
Expert Reply:
There are a number of factors involved when converting a semi 7-way to an RV 7-way. Semis generally use a 7-pin round pin socket, similar to # PK11720. And RV style 7-way uses blades, like # PK12706. We do not offer any pre-made adapters to make this conversion that will carry all of the electrical functions required by the RV.
Another thing to be aware of is fifth wheel trailers use a combined wiring system where the brake lights and turn signals are on circuit. Your semi connector uses a separate wiring system where the brake and turns are on different circuits.
Also the brakes on your trailer are likely electric brakes and your semi 7-way is not wired to power them. The brakes on a semi are typically air brakes, and are controlled through a different connector than the 7-way. You will need to install an electric brake controller in the cab of your truck wired to the RV style 7-way to power your brakes.
If you want to keep your existing connector on your truck you can splice into the wiring. Or if you have no use for it you can cut it off completely.
To combine the tail light circuits of the semi you'll need a converter # 119250KIT. To install the actual RV 7-way use install kit # ETBC7 which will also include everything to install the brake controller. For a brake controller you can use the Tekonsha Prodigy P2 # 90885. You'll likely need additional wire # 16-4B-1 for 16 gauge which can be used on all tail light wires.
Attached you'll find a help article on trailer wiring as well as a diagram showing how an RV 7-way connector is wired.
Product Page this Question was Asked From
Hopkins Endurance Quick-Install 7-Way Trailer Connector with Universal Pigtail Harness - Vehicle End
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- Universal Fit
- 4 Flat
- 7 Blade
- Plug and Lead
- Splice-In
- Hopkins
more information >
Featured Help Information
Instructions
Miscellaneous Media






Continue Researching
- Shop: Trailer Wiring
- Shop: Vehicle Tow Bar Wiring
- Shop: Roadmaster Brite-Lite 3-to-2 Tail Light Converter for Towed Vehicles
- Shop: Brake Controller
- Shop: ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit
- Search Results: brake controller
- Search Results: curt echo wireless brake controller
- Search Results: fifth wheel
- Search Results: 7 pin
- Q&A: How to Make an Adapter to Go from Semi Truck 7-Way Round to RV Style 7-Way Blade on Trailer
- Search Results: 7 blade to 7 round custom fit vehicle wiring
- Search Results: chain
- Video: Curt 2 to 3 Wire Tail Light Converter: The Breakdown
- Shop: Pollak HD, 7-Pole Round Pin Connector w/Cable Guard
- Search Results: 2010a
- Shop: Curt RVi Series Shadow 2 Flat Tow Brake System - Wireless Monitor - Proportional - Fixed
- Shop: TowSmart ProClass 7-Blade Trailer Connector w/ Wire Tester - Trailer End
- Shop: Pollak Trailer Connector Adapter - Vehicle End - 7-Pole Round to 7-Way Blade
- Shop: Gooseneck to 5th Wheel Trailer Coupler Adapter - Inner Tube - Round - 25K lbs
- Shop: Suspension Enhancement
- Shop: Trailer Hitch
- Shop: Vehicle Tow Bar Brake System
- Shop: Camper Tie-Downs
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Q&A: Wiring Diagram for a 1997 Peterbilt Semi Tractor with 7-Pin Round Connector
- Article: Trailer Wiring Diagrams
- Q&A: Need Replacement For Dometic 3313195.012 Thermostat
- Video: Mount: Air Lift LoadLifter 7500 XL Ultimate Air Helper Springs on a 2020 Ram 2500
- Video: All You Need to Know About the Air Lift WirelessONE Compressor System for Air Helper Springs
- Video: Installation Guide for the etrailer Invisible Base Plate Kit on a 2018 Ford F-150


