Is trailer wiring necessary?

The trailer hitch will allow you to tow a trailer but you will need a separate wiring harness to power the lights on the trailer. The most common harness is a 4-Flat. This is what you will find on small trailers that do not have electric brakes but do have brake lights, running lights, and turn signals.

How long does it take to wire a boat trailer?

This is a four to five-hour project, but it doesn’t take much skill to complete. It certainly isn’t as complicated as rewiring used outdoor boat motors. Here’s a step-by-step on how to rewire a boat trailer.

What do I need to rewire my boat trailer?

Disconnect the lights and remove the old harness, noting how the wires were secured. It may be necessary to run the wires inside a tubular frame member or rings along the frame. Use the old wires to pull the new ones through before making any connections.

Where does the blue wire go on a boat trailer?

The harness has two sets of combo wires: Yellow and brown run along the left-side frame; green and brown run along the right side. The white ground wire connects to any bolt behind the coupler. The blue wire (on a flat-five) connects to the solenoid on the surge actuator. 3. Connect the Running Lights

How do you connect brake lights to a boat trailer?

Seal the connection with a section of heat-shrink tubing. Check the ground for each light. Some ground through a connecting bolt, others with a separate white wire to the trailer frame — both subject to corrosion-induced failures. 4. Connect the Brake/Turn Lights

How many wires are in a flat four trailer?

The traditional flat-four has five (yes, five) color-coded wires. Newer flat-five plugs have an extra (blue) wire for deactivating the surge actuator in reverse for trailers with disc brakes. Make sure you have sufficient wire length to reach all of the trailer lights, including the clearance lights on the rear cross member.