What is the Difference Between a 4-Way and 7-Way Trailer Connector

Expert Reply:

A 4-Way trailer connector has the basic lighting functions only; running lights, left turn signal and brake lights, right turn signal and brake lights, and ground.

A 7-Way has these functions and a 12 volt circuit, a circuit for electric trailer brakes (requires a brake controller in the vehicle), and a reverse light or auxiliary power circuit.

There are other types of connectors as well. I have included a link to our help article that shows and explains the various connector types.