https://i.imgur.com/bQulQ6Z.jpg This is our water heater in our camper. We're not getting any hot water out of it whatsoever. The "Water Heater" switch on the switchboard lights up, so it seems t...
There should be a small fuse on the control board. If you had a meter (they're not very expensive and recommended equipment for all RVers) you could pull it out and test it.
If it's a new unit, can you see if the dealer can help? If it's not the fuse, it could be the control module itself and that's about $100 more or less depending if you get it from Amazon or an RV stealer.