Kenmore Side by Side Freezing up

I have scoured this forum to try to determine what my issue is. Let me give you some history, freezer works beautifully, frig side gets warm. I removed the panel covering the coils and found that it was a solid block of ice. This was not allow air to flow to the frig, I manually defrost with hair dryer and put it all back together and approximately 1 month later, same thing. I defrosted yesterday and put parts in place to allow air flow. Allowed it to run over night and just checked the thermostat with an ohm meter and had 3 ohms. Not sure if this is bad or good as I have not found a range it should be in. I disassembled every panel I could find trying to locate a defrost control board and could not find one. I do not see the defrost lines heating up when it is unplugged and started over. The model number is 106.542.19300. Any ideas?

Thanks in advance
Brian