One day the ice cream in the freezer seemed mushy, but the ice was still frozen. There was not water in the ice bin. However, the problem resolved itself. This suggested that the defrost timer had become stuck for an extended time, but then continued to run. The fact that the freezer went back to frozen, implies that all the components of the cooling loop (compressor, condenser & fan, evaporator & fan) were fine. It was possible that the problem was caused by a bad defrost (?evaporator?) thermostat but everything I saw on line suggested that the defrost timer is the culprit about 40 - 50% of the time. Anyway, I followed the instructions in the on-line video at this site for replacing the defrost timer and it was easy. It would have only taken 15 minutes, but I spent a while reading the defrost timer instructions and hunting down a schematic for my refrigerator, to determine which pin the loose wire should go on.
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