Methods for monitoring a sensor of a refrigerator appliance are provided. The methods include activating an auto-fill feature of the refrigerator appliance and receiving a signal from a sensor of the refrigerator appliance. The method also includes displaying a message on a display of the refrigerator appliance if the sensor does not detect the container within the dispenser recess. The message can provide a user with feedback regarding the auto-fill feature and assist the user with properly operating the auto-fill feature.