.When you open the door freezer door will get stopped and so, no sound. It will work only when door is closed. Fan sound comes due to malfunction of defrost. If defrost does in right time it won't happens. Unplug and let fridge get defrost all icing. After 3 to 4 hrs,start run again, and set temp @ 5degree freezer. It will start cooling fridge compartment also. But, this is a temerory solution. To solve permanently, find out why defrost not functioned properly?
Follow this steps.
Check defrost timer working which is back of the refrigerator down corner. By with small tip screw driver in some models located in the ceiling of the fresh foodsection or behind the cold control cover. In the defrost timer,slowly turn the screw like wheel in the middle of the defrost timer withstraight screwdriver until the fridge shuts off. Now it's in defrost. If thedefrost heater(s) starts, replace the defrost timer and defrost thermostat. Ifthe heater(s) does not start, unplug wire cord to check ohm test for continuityof heater. If continuity is there, plug cord wire which gives power 120volts(check specification) to heater. If heater no starts, bypass defrost thermostatby join the 2 wires in the defrost thermostat. If the heater now comes on,replace the defrost timer and defrost thermostat. If the heater itself is bad,replace it. Thanks and hope helpful.