[fixmyfrige]

Can someone please tell us what we can do to fix this. The back panel and behind it keep freezing solid.

[woodchuck]

It freezes because of a failure of in your defrost system.check defrost timer, defrost heater, defrost thermostat

In your unit it has the adaptive defrost control instead of the timer.. It senses when to defrost based on how many times and for how long the door is opened. It's more energy efficient but there does seem to be lots of problems with the board. If the heater and thermostat are good it will be the control.
Refrigerator Repair Guide: How To Fix a Refrigerator - ACME HOW TO.com