I have the RM 2201 and I know that it is designed to shut the pilot light
& gas off if there is a problem with the supply. You may need to do a search here on cleaning up the pipes etc - something as simple as a spider web can be the issue. If it works on the 12 volt thats good news as that points to an issue with propane
supply and not the fridge
I do sometimes have problems getting mine to light
and stay light when I first start it up - most often if it has not been used in a long time. I need to keep the red pilot button pushed in for sometime after the flame lights
or it will go out. Often takes a couple of tries. It did give me a bit more grief than normal getting it to light on a recent trip but suspect that was due to being over 8000' and propane doesnt burn so well. At close to sea level it started and stayed light first try this past week-end - go figure.