Suffered a total thaw with no cooling. So I:
Just replaced the mother board and everything seemed peachy. Now the freezer back panel and coils are frozen. Evap fan is staying on keeping the fridge half way good, but the food in the freezer is thawed.

Ice at the bottom of the coils was the most dense surrounding the heater element.

I carefully de iced the coils and replaced the Defrost thermostat as I had purchased it before paying a repairman to fix.

Plugged the fridge back in coils beggining to frost up slowly from the bottom up.

My next thought is the heater itself which I will observe with the freezer empty and panel off.

For now I'll look up heater testing methods. Any advice greatly apperciated.

After a few hours of operation the freezer froze a bottle of water and then went quiet. I opened the freezer and felt the bottom tray where the heater is and it was hot. After about 10 or 12 minutes it began the cooling cycle again. Does this sound like normal operation?

This is the first cooling cycle since I replaced the defrost thermostat. I'll take the freezer back panel off tomorrow night and see what it looks like before I restock it with food.