Had a similar problem. Mine unlocked (or tried to) normally after I switched off the car and opened the door to climb out. Try opening and closing your driver door and note if the door tries to unlock. If it does, take off your door panel, unclip the white wireplug that leads into the door lock/unlock button. Inside the wireplug are copper leads. Sometimes someone took off the door panel and bent one of the pins when they put it back. The pin then only makes partial contact and causes problems with your central locking.
Prof
June 2009