My freezer one day stopped freezing and I had to move a bunch of stuff to other freezers. Control panel did not respond properly. I unplugged it for an hour or so and plugged it back in. Some panel functionality returned but not 100%. Freezer then went into deep freeze mode and plunged to -18 F. Gave it another rest and for two days it held pretty close to -2 according to logging thermometer I placed in it. Then back to about -15...
Ordered and replaced the control board and now it's functioning properly, maintaining -2 average and defrost cycles are apparent.
The board was easy to replace although I did damage the bezel getting it off. I cracked a couple of the "ears" that hold the bezel to the door. It seems like there's enough to keep it together but if you are picky you might want to locate the bezel replacement when replacing this part. All you need is electrical tape to protect the door surface and a 1-1/2" putty knife to pry the bezel off the door and work the tabs holding the board in the bezel. 10-15 minute repair, tops.