How to Repair a Camper Travel Trailer Electrical System Hi, Randy: I am brand new to camping and purchased a 2007 Layton travel trailer. The unit was rebuilt. When examining the electrical system, I found a double tapped wire at one breaker (easy fix) and underneath the breaker box anchored to the floor is a 10 terminal bus bar.Author: Randy Godwin Understanding the R.V. Electrical System - YouTube Click to view on Bing8:03Porter's R.V.s, an Oregon R.V. dealer since 1966! Watch this video to understand the basics of the R.V. 12V and 120V systems. Representing such brands as Cougar Travel Trailers and 5th wheels, Jay Flight travel trailers, Author: PortersRVViews: 175K Jayco Trailer Wiring Diagram | Free Wiring Diagram Variety of jayco trailer wiring diagram. A wiring diagram is a streamlined standard pictorial depiction of an electrical circuit. It shows the elements of the circuit as streamlined shapes, and the power as well as signal connections in between the devices.