One problem related to door has been reported for the 1999 Mercury Sable. The most recently reported issues are listed below.
Was driving along when the door came open by itself. After the door was shut the locks "locked " again. The door and others were already "locked". The same thing happend this morning except the door was just ajar it didn't completely open. I was traveling about 25 mph when it happened today. When I stopped and shut the door, the locks didn't reset or click as they did last night.