In this video, I replace my old worn looking trailer breakaway safety switch with a new one. I explain the wiring and test it.
The breakaway switch is there in case the fifth-wheel trailer, and the truck becomes separated during towing. If that happens, a safety line will pull the plunger out, and the switch will activate the trailer brakes.
I also give the tow cable connectors a clean and redo a ground wire with a bit of corrosion on it.