Googled the problem and followed troubleshooting suggestions. Discovered that the defrost timer was not turning, stuck in cold mode. I unplugged the fridge to melt ice dam and having used AppliancePartsPros in the past I went online and found the part for my model on sale so I ordered it. Part arrived at my door the next day. I then watched the repair video provided by AppliancePartsPros and replaced the defective part in less in about 30-45 minutes. The refrigerator has been running problem free for 3 days. Would highly recommend AppliancePartsPros.com to all Do it yourselfers.