I've got an el wagon as well and the only way that would happen carol is if the drivers door is open. If the door IS closed properly and it still wont lock then theres something wrong with the door lock, either electronically or mechanically. You may have to get the door looked at and have the trim removed to get a better look at whats happening, and see if anythings in the door locks way- stopping it from locking. If your not mechanically minded or know someone who is i suggest taking it to a mechanic.
Lloyd
May 2009