Installing 3-Way Switches in Camper Van (Diagram, Images)

Here is how I wired mine for that exact purpose, But I also wanted the switch to illuminate with the lights in the bed as an indicator. End result with my setup is one light on my switch comes on with the headlights, the other when the bed lights are on, no matter what position the in cab switch is in. Only difference in wiring is that I tied the dash lights to the lower light and the bed lights to the upper light in the switch. That way the words illuminate with the headlights. After I did this I also discovered that tapping into the dash light circuits also ties into the dimmer.