i have a 1992 740 wagon. i cannot open the drivers side door with the key. i have to go around to the passenger front side and open with the key..then reach in to unlock the drivers door (and the rest (power locks.) In other words the lock on the drivers side seems to be completely worn out.. it used to work but got harder and harder to turn till finally it refuses to turn at all. any ideas?

 

If it were my car, I would remove the door panel inside the car and visually inspect it. Sounds like the mechanism just got worn out over time. There are a couple screws and some push pins to remove the panel. Let us know what you find.

 

Could also be a siezed lock cylinder.