I am doing a long distance fridge troubleshoot by phone. I was told that the compressor and fans in a KitchenAid KBFA20ERSS01 appear to be running, but that the temperatures displayed were 70º in the fridge and 61º in the freezer. I was also told that the back of the freezer compartment did not feel cold. 70º is about the ambient temperature in the area today.
If the defrost mechanism is defective frost would build up around the evaporator coil and air circulation would cease, but the back of the freezer wall should feel cold.
The 9º temperature difference between the fridge and the freezer compartments could be explained by the food in the freezer giving off the last of the cold (the problem was noticed yesterday).
This scenario has all the symptoms of a loss of coolant. The onset was sudden, not gradual. Could there be any other cause for such symptoms?