The freezer section was getting too cold and constantly running. The digital display was reading 9 below. The fresh food compartment was not cooling properly. It was reading 45 degrees plus. Once the defroster turned on the freezer section would get too warm and melt the items inside the freezer. This process was producing frost that built up on everything. My ice maker compartment would freezer over and become a frozen cluster of ice that was not useable. I put two thermometers in the refrigerator, to monitor the temperatures in both compartments. The thermometers indicated vast differences in the digital reading and what the thermometers was reading. I suspected a temperature sensor was bad.
I replaced the two temperature sensors in the freezer compartment. One was behind the access plate for the evaporator and the second one was on the inside wall. I also replaced the defrost thermostat. When I removed the access plate I used a hair dryer to melt and dry the evaporator coils. This took about 45 minutes. Replacing the temperature sensor was straight forward; similar to wiring a stereo speaker. The access was a little bit tight. The defroster thermostat was just as easy. I made sure the freezer compartment was dry with the hair dryer and put it all back together, plug it back in. After about two hours the temperature was down below 32 degrees and after 12 hours down to zero. It has held the temperature constantly since I replaced the three sensors. No more frost either.