I also had similar problem once on my Dometic fridge. Having had electrical experience, I always carried various testing equipment with me (digital VOM and clamp-on ammeter). I first located the wires going to the heater element and, using the ammeter, found it was drawing no current. The correct voltage was there, so the obvious conclusion was the heater element had opened (i.e. burned out). I managed to obtain a similar replacement and got the fridge working again. For me, it was a simple fix.