I replaced the blower motor that sits behind the back panel in the freezer that circulates the air from the cooling coils down to the refrigerator portion. The first symptoms were warm fridge and cold freezer. When I opened up the panels and got to the cooling coils, they were a block of ice that extended into the drain tube and into the vent holes down to the fridge. A lot of defrosting had to take place before I could fully disassemble the panel and get to the coils. Then a lot more defrosting to finally clear the coils and drain tube. The blower motor took care of it completely.