Trailer Wiring: Things to Know

Proper trailer wiring is not only a guarantee, that you will not get a ticket from a police officer for being not visible enough on the road, but also means of your own safety. The better the other drivers see you, the safer it is to tow a trailer at night. When the trailer is wired properly, the trailer lights work right and show the traffic behind you, when you are about to turn, stop or back up.

Trailer Wiring: Types of Connectors

Types of trailer connectors depend on the truck specs. So, the wiring diagram of the trailer lights will also differ. Here are the most common types of trailer lights of connectors that are installed on the U.S. vehicles.

  1. 4-way connector;
  2. 5-way connector;
  3. 6-way connector;
  4. 7-way connector.
Trailer connectors in North America

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Depending on the trailer wiring type, the connectors power the following:

  • Right Turn Lights/Brakes;
  • Left Turn Lights/Brakes;
  • Tail Lights/Running Lights;
  • Ground Wire;
  • Reverse lights;
  • 12V power supply;
  • Backup/reverse lights.

Check out detailed description of trailer wiring diagrams here:

MudFlap Systems by Make

Mud Flaps for Popular Trucks