What is a Tekonsha wiring diagram used for?

A Tekonsha wiring diagram is a detailed visual manual on how to install a brake controller in a Tekonsha Voyager trailer. The diagram shows where the each of the controller's four wires connect to the vehicle.

Each of the four wires in the Tekonsha Voyager brake controller wiring diagram has a different color and function. The white wire is the ground and connects to the negative terminal on the battery, black connects to the positive terminal, red leads to the switch that controls the brake light, and the blue wire acts as a brake feed that connects to the trailer brakes.