The 10 most common part(s) or condition(s) which contribute to the symptom Refrigerator not cold enough are listed below.
Condensor fan motor
If the refrigerator is not cold enough there might be something caught in the condenser fan motor blade, or the condenser fan motor might be defective. The condenser fan motor draws air over the condenser coils to cool them. The condenser fan motor is located underneath the refrigerator near the back. Pull the refrigerator out from the wall and remove the access panel to access it. 

Start Relay
If the refrigerator is not cold enough, the start relay may be defective. The start relay is a small device mounted to the side of the refrigeration compressor. It provides power to the run winding along with the start winding for a split second at start-up to help get the refrigeration compressor started. If the start relay is defective the refrigeration compressor may run intermittently or not at all and the refrigerator will not get cold enough. The start relay should be replaced if defective.
 Temperature Control Thermostat
 If the refrigerator does not get cold enough the refrigeration temperature control thermostat might be defective. The refrigeration  thermostat allows power to flow through to the refrigeration compressor, evaporator fan and condenser fan. If the cooling system fans and refrigeration compressor are running, but the refrigerator or freezer is not cooling correctly check for an airflow or defrost system problem.

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