7 Pin Trailer Plug Pinout May 13, 2019 Narva . Â Select Plug & Socket Type Our trailer plug wiring guide is complete with a colour coded and numbered system to help you connect your trailer to your vehicle. Need... www.narva.com.au One Way Switch DiagramLow Voltage Wiring BasicsUsb Mouse Wire Color CodeBlack Wire Neutral2 3 Way Switches With One LightWire A Light Switch DiagramBlack Light SwitchTrailer Light Wiring Troubleshooting