I've never seen one yet when the actuator itself fails. Normally, the temperature control door breaks where it connects to the actuator. Replacing the door is a pretty big job that involves removing the center console, the instrument panel and seperating the plentum case to remove the broken door and drop the new one in. Figure a solid weekend if you've never done it yourself, or somewhere from $7-800 worth of labor for your friendly neighborhood Ford or Lincoln-Mercury dealership to do it.
!@#$ the language filter.