Following the excellent video I determined that I needed to replace the defrost heater and thermostat. I ordered them online and selected overnight shipping hoping to salvage the contents of the fridge with dry ice. I got the parts and installed them easily by referring often to video. I plugged in the fridge and allowed it to cool to proper temp and reloaded the food and saved almost everything. AppliancePartsPros.com will be my go to website for any future repairs.