If this is a twin compressor + Twin thermostat model, I can imagine that the fridge-side compressor / pump or thermostat is faulty whilst those for the freezer are OK.
If this is a single compressor +/or single thermostat model, it may be that the refrigerant pipes/tubes or the air ways are blocked. That is, the themostat and compressor are fine but the refrigerant or the cooled air is there but is not being circulated.
Silver Fox 56, August 2005