There is one compressor that serves both the freezer
and refridgerator compartments. You need to confirm if the evaporator fan in the freezer compartment is working. When you open the door to the freezer, you should see and hear the evaporator fan in the freezer compartment running. Particularly if there is a demand on the unit through the thermostat setting. If the evaporator fan is not operating, you can check the evaporator fan motor with a volt meter to see if it's getting power. If its getting voltage, but not operating, you need to replace the evaporator fan motor in the freezer compartment. There are 3 wires that attach to the evaporator fan motor. One hot wire, one neutral wire and one ground wire. The ground wire is usually marked green
, the voltage wire is usually marked black and the common wire is usually marked white. You should get a reading on your volt meter of a voltage from the hot post to the neutral or from the hot to the ground. If it is getting power but will not operate, then it is definitely a bad fan motor that would need to be replaced.