RV Repair: Fridge, obscure switch, dometic fridge

Question
dometic fridge will not work when plugged in.

Answer
I am guessing you mean you plugged a regular fridge into the outlet that is for the camper fridge, and it still does not work.  If that is so, it may make you wonder if the outlet is dead.  Maybe a breaker, bad outlet, obscure switch, GFCI, etc.  You can get an AC outlet tester from a dollar store.  Try the outlet to see if power is there.  Does the regular fridge work with an extension cord?  Is the old fridge DC?

It is possible your fridge outlet is set up for a DC motor?   The DC inverter could have gone bad.  Or the old DC fridge went bad, the new AC fridge won't work on DC power, and you actually need a DC Fridge.  If that is the case, you will want to run a separate/new outlet from a power source for the AC fridge. I would come right off the main breaker panel if there is room for another circuit.