Refrigerator not cooling, heavy frost build-up in freezer compartment

First I unplugged the refrigerator.
Then removed the outer plastic cover inside the refrigerator compartment...it just snaps in & out.
Used a nutdriver to remove screws from the inner cover & let that just hang down.
Located the Adaptive Defrost Timer & unplugged the wiring harness.
Removed the old Adaptive Defrost Timer & replaced it with the new one.
Reassembled everything in reverse order as stated above.
Then I plugged the refrigerator back in & set the control setting to the coldest settings.
The freezer side was cooling down much quicker than the refrigerator compartment, but after a couple of hours, everything was working very well.
Note: The freezer compartment needs to be totally defrosted
sometime before or after this repair is made, which can take a whole day or better!