Answer Mike, You will want to pull the rear cover off inside the freezer compartment and check the evaporator coils for being impacted with ice. If they are impacted with ice then there is a defrost issue and you will need to check for continuity on the defrost thermostat and defrost timer. If these check good for continuity then the defrost timer would be the issue. If there is no continuity on the heater or the thermostat then replace the part that does not show continuity. Read More... Answered by AppliancePartsPros.com | Friday, May 27, 2016