After calling the appliance repair service, the technician said that the Control Defrost Module needs to be replaced, and it'll take 4-5 days to complete the repair. I didn't want to wait that long, so I ordered the part (this is my second time ordering from APP, last time was a washer part). In the mean time I removed the back panel of the freezer to discover a very thick ice build up. I let it defrost overnight, and by the time the part arrived the next day, in less that 24 hours, I removed the old "fried" Control Defrost Module and installed the new one, and now the fridge is running as new again. Many thanks to Appliance Parts Pros for their great service and reasonable prices.