Trailer Wiring Diagrams | etrailer Trailer Wiring Connectors. Various connectors are available from four to seven pins that allow for the transfer of power for the lighting as well as auxiliary functions such as an electric trailer brake controller, backup lights, or a 12V power supply for a winch or interior trailer lights. Trailer Wiring Diagram - Wiring Diagrams For Trailers Rewiring or wiring a trailer? Not sure about the wiring the 7 pin connections? Use this handy trailer wiring diagram for a quick reference for various electrical connections for trailers. They often use bonded wires for a reliable connection and have rubber construction to protect against the elements. WIRING DIAGRAM TAILGATE ( TRAILER) PDF file1 2 3 4 5 6 7 wiring diagram tailgate ( trailer) sabs 1327 - 1981 1.----- left indicator -----yellow 1 2.----- auxiliary-----blue 3.-----earth-----white Trailer Wiring Diagram - Venter Trailers Trailer Wiring Diagram. Trailer Wiring Diagram 5 Pin Trailer Wiring | etrailer Establish a secure connection between your trailer and tow vehicle with this chrome-plated, 5-pole plug. Split brass pins ensure minimum voltage drop, and pull grips enable easy insertion and removal. and Brake Lights Red - Auxiliary Circuit Brown - Tail Lights 1-Year limited warranty 11-501P Pollak 5-Way, Round Pin Trailer Wiring Connector How to Install Trailer Wiring | Color Coded Diagrams How to Install Trailer Wiring on Your Vehicle. with Color-Coded Diagrams! Any vehicle towing a trailer requires a trailer wiring harness to safely connect the taillights, turn signals, brake lights and other necessary electrical systems.