A Quick Guide to Trailer Connectors

This guide will walk you through the different types of trailer connectors and their uses, from 4-pin connectors to 7-pin connectors and everything in between. Towlos has a variety of trailer types available to rent. Understanding what type of connector your truck or SUV will need is an important part of a good trailer rental experience! Included in this article is information on what types of trailers have the connectors in question. Hopefully this helps you understand what type of connector or adapter you will need to tow a trailer you rent on Towlos!

4-Way Flat Connectors (4 Pin)

Small trailers commonly use the 4-Way Flat Connectors. They usually handle three basic lighting functions – turn signals, brake lights, and tail lights. A fourth pin provides a ground connection.

5-Way Flat Connectors (5 Pin)

Boat trailers and marine applications usually employ these connectors. Besides the functions provided by 4-way connectors, an additional circuit handles the reverse lights to disengage the surge brakes when backing up.

6-Way Round Connectors (6 Pin)

Larger trailers, such as horse trailers or car trailers, use 6-Way Round Connectors. They provide the basic lighting functions, electric brakes, a power supply for interior lights or battery charges, and an auxiliary circuit.

7-Way RV Blade Connectors (7 Pin)

Large trailers like RVs use 7-Way RV Blade Connectors. These offer the same circuits as the 6-way connector but with an additional circuit for reverse lights or auxiliary power.

7-Way Round (Heavy Duty) Connectors (7 Pin)

Heavy-duty applications often require 7-Way Round Connectors. They include connections for an electric brake controller, backup lights, or auxiliary power.

European 7-Way Round (ISO 1724, 7 Pin)

This European standard, while similar to the 7-way round connectors used in North America, varies in terms of the pin arrangement and signal assignments.

European 13-Way Round (ISO 11446, 13 Pin)

Increasingly becoming the standard for trailers and caravans in Europe, the European 13-Way Round Connector provides basic functions as well as refrigerator power, battery charging, reversing lights, and more.

Remember, these are general descriptions, and the specific pin functions may vary based on the manufacturer or model of the vehicle or trailer. Always double-check the specific requirements for your vehicle and trailer to ensure you have the correct connector.

Andrew Rains is a race car driver and driving coach. Having been a professional in motorsports for over a decade, he has repeatedly seen the need for easy access to the right trailer for getting your car to the race track. Andrew is passionate about lowering the barrier to entry for motorsports participants! He currently lives in Birmingham, AL.