I've done a lot of research only to not find the right answers. I was always taught to try the simple things first.
We'll awhile back I thought my beer wasn't getting as cold as I like so, I turned the thermostat to max cool. We'll still not cold enough so, I looked and saw that there is two temp controls. One for the fridge and one for the freezer. Well let's try turning the freezer to max cool. Things started getting worst, warmer. 40 degrees. After a couple of months of thinking my fridge was on it's last legs I decided to web trouble shoot.
One recommended cure form the experts was to clean the condenser coils followed by checking the fan motor. Well let's just hold on here a minute. I doesn't a cold cold freezer tell you that the coils and fan are all right? Next test the defrost timer. Whoa hold on there. If there was trouble with the defrost the freezer wouldn't be cold right??
Next test rip the freezer a part to check the fan and if the coils are frozen up.

OK OK here's what the problem was. Looking at the control for the freezer temp I found out that all it does when you put the freezer colder is it is nothing more than cover over the hole were the cold air comes in directing more cold air to the freezer and less to the fridge. Do you see what I mean? All I did was turn the freezer control the other way to warmer opening the little door to let the cold air in to the fridge and a day later the thermometer went from 40 degrees to 20 degrees and the freezer's doing just fine. Hey, the simple things. I hope this helps someone else. H