Well with a lot of help from the world wide web and my friends from AppliancePartsPros.com, I was able to determine the source of the problem, which was the defrost thermostat. However, due to the disassembly involved to get to it, I decide to also change a couple of other parts involved in the defrost process, which are also located in the same compartment as the defrost thermostat. These parts were the thermistor and the defrost heater. Thanks to AppliancePartsPros.com, they had the parts I needed in stock and rushed them out to me the next business day. I swapped out the parts in about an hour and the fridge was back in business in no time, running like new ever since. My next order of business with this refrigerator is replacing both door gaskets.