Hi...My freezer back wall keeps freezing up and the freezer never shuts off. The fridge and freezer are cooling everything fine. I took the back panel off in the freezer, defrosted all of the ice with hairdryers. A repair man came to repair it, and he said the quote, "defrost control board" in the back of the fridge needed to be replaced, for $320!!! He said newer electronic model refridgerators have electric panels in teh back of the fridge that can go out. I kindly told him I would not need his services.

I, however, after researching this website and others, think the problem might be either the defrost thermostat or whatever is considered to be the "defrost timer" in these newer models (there are temperature sensors inside the freezer and fridge). I understand newer models do not have defrost timers in them.

The defrost heater is working, as the repair man showed me its red light that was glowing when the fridge was on.
The repair man did say defrosting the freezer would help, yet the freezer would just start freezing up again in a week.

Can you offer any indication if the problem could be the defrost thermostat or a temperature sensor in the freezer, or does the electronic computer panel in the back need to be replaced?
Thank you kindly for any response!

Thanks for your information. Since I defrosted all of the ice off the coils behind the freezer wall, the freezer has been running normal (it's not constantly running). So, hopefully we won't have to replace the motherboard and thermister. But, it's good to know what was going on with the freezer. Thank you again!