AFAIK, the switch is before the board, so first you should pull the switch with its red light, jumper the switch wires (not the light's) and see if that makes it all work.
Next is the connection of the wires to/from the switch and board at the board. I had an Atwood where that was the problem. Unplugged and plugged back to the board, which cleaned the contacts, and then the red light at the switch came on and everything worked.