Converting a Semi 7-Way Trailer Connector to an RV 7-Way Trailer Connector
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.
Products Referenced in This Question
ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Universal Fit
- 4 Flat
- Tekonsha
more information >
Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LED Display
- Up to 360 Degrees
- Tekonsha
more information >
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
more information >
Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 7 Round - Round
- Pollak
more information >
Pollak Black Plastic, 7-Pole, RV-Style Trailer Connector - Trailer End
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- Plug Only
- 7 Round - Blade
- Pollak
more information >
Product Page this Question was Asked From
Hopkins Endurance Quick-Install 7-Way Trailer Connector with Universal Pigtail Harness - Vehicle End
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
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