Answer Hi Ben. I presume you mean the freezer is not 0° anymore. Can you see if the back wall of the freezer is frosted up w/ frost ? Open this cover and you may see the coils completely frozen over ? If so the shut the door and get a large blade screwdriver. Turn it until you get to the first heavy click. This now will shut off the compressor and fans allowing the defrost circuit to come on. Wait a minute and then look into the bottom of the freezer coils. Is the heater coming on ? If so then replace the defrost timer part # 215846602. You will need to test the defrost thermostat part # 5303918202 clipped to the top rt. evaporator (fzr)coils. Use a volt/ohm meter part # MA-DM1 to make sure your defrost timer sends the 120 vac to the thermostat on one side and the white wire at the heater. Make sure the heater has approx. 8-18ohms resistance. If open then the heater needs replaced part # 5303918208. Thank You. Read More... Answered by AppliancePartsPros.com | Saturday, February 25, 2012