Cardinal Luxury control panel.
 

On our new 345RLX the main control panel is self explanatory except for the three rocker switches towards the bottom. The first two control the lights above the island and the lights above the microwave wall cabinets. The last one does nothing that I can tell. Any ideas what it’s supposed to do?

This is a total guess on my part but check and see if the switch controls an outlet that a light might be plugged into like I said a total guess I'm sure someone on the forum will the answer.

tank heaters?

Could be out side lights. Later RJD

Did you check to see if it was your WI-FI Ranger? Just curious.

Funny I've been wondering the same thing since we bought our 21 345rlx last week. I kept hoping it was for the rear view camera, but i got the camera in today and sadly its not that. My 16 Jayco had a switch just for the rear camera. I guess the mystery continues lol.

It may turn on your electric water heater .Take the water CV heater cover off and see if there is an electric off and on switch . If not that may be it .

It appears to be for the Winegard Air 360+