Well, not knowing refrigerators too well I have always assumed it was the refrigerator motor because the refrigerator is the section that loses all it's coolness while the freezer just stays frozen up top... i hope that helps you....
You have a defrost problem it is one of three things.
1/ Defrost heater
2/ Defrost termination switch
3/ Defrost timer
Its not very expensive to repair the unit.The most it would cost is $200.
Does that $200 include parts and labor?
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