Dometic RM4332S not working 240v or 12v

Our AS is a 2003 Executive and normally very reliable but now the Dometic RM4233S 3 way fridge freezer has stopped working on both 240v EHU and 12v when driving. It still works on gas so its not the end of the world yet. I have checked all the fuses I can find, under the drivers seat (Habitation battery) and in the engine bay, but all are fine. The fridge ignites when on gas as it should, so there is electricical current to the fridge of some description. Before it gets taken out to test both heating elements can anyone suggest the cause of the electrical problem?
I did a bit of internet searching and find the replacement fridge frezer, RM5330, is also discontinued. The VITRIFRIGO VTR5070 DG is the only reccomended alternative but at £1,450 in vat its very expensive. Anyone had any experience with this fridge?

Do you have the fuse panel behind the drivers seat , if you do remove the panel and check the back for loose connections, your van maybe too old though for this panel