Re: Entire 12V system not working
Reply #3 –
most coaches have a set of switches just inside the door on the left wall for steps, basement locks, patio light, etc. Somewhat separate from that on the same wall is possibly a spring loaded switch labeled Battery disconnect or Disconnect 12V. It can be inadvertently hit by pets and humans. Its purpose is to kill all battery power to the house during storage in order to minimize parasitic discharge. Sounds like that's your problem here. Just press it and release.
Roger