CONCERN: Customer reports refrigerator is not working properly. CAUSE: Found refrigerator defrost timer failed. Customer also needed very invasive defrost service. Water method used. CORRECTION: Replaced refrigerator defrost timer and tested. Operation now normal. CONCERN: Customer reports refrigerator section is not getting cold but freezer is still working properly. CAUSE: Found back panel and evaporator coils covered in frost. Tested the refrigerator defrost bi-metal thermostat for continuity, refrigerator defrost bi-metal continuity failed test. Refrigerator defrost bi-metal has electrical short. CORRECTION: Defrosted refrigerator evaporator coils and replaced defrost bi-metal thermostat. Operation now normal.