1995 Lincoln Continental Problem HELP!

Question

I have a 1995 Lincoln that sometimes a message on the message center says drivers door ajar(when it's not)and the dome light comes on but will go off when the car is moving but comes on again at every stop sign and the electric door locks will not stay locked. When it does this I undo the negative post on the battery and leave it over night and hook it back up in the morning and everything works normal for about a week and it does it again. What could this problem be? HELP!!!!!