[tentcamper]

the AC breakers and DC power board should be on the hall wall where the fridge is. You have to open the panel

the TM comes with a propane detector no carbon detector. I think it should be on your model a few inchs from the floor on the small bathroom wall next to the kitchen sink. The rv industry has been install the detectors long before 1995. If you don't have one there check and see if your have some holes there. The units go bad and beep and some one may have removed it.

The status board (battery power/water levels). I would check and see if you have 12V DC going to the test switch. Then I would push the switch and see if you have 12V DC on the other side of the switch. Problem might be no 12V DC or a bad switch.