Unplug the electrical power first:
Inside the freezer section, look through the lower slots in the lower rear panel to see if the evaporator coils are all iced up or have just a slight frost coating.
If coils are all iced up, you have a defrost problem (if this is a frost free unit). This could be defrost timer or defrost thermostat problem.
If the coils have just a coating of frost, then the compressor and defrost cyle are ok and the problem may be that the evaporator fan is not running. The rear panel would have to be removed (with unit first being unplugged). And, then plugged back in to see if evaporator fan is running (DO NOT stick hands, etc inside with rear panel off and unit plugged in!!)
Also, check to see if coils underneath refrigerator are clean.
If you still can't determine, please let me know what checks showed.
Paul S., June 2012
