Doors lock with no reason!

I have a 1990 735iL and I am trying to bring it to near perfect condition. I'm close but the door lock system seems to have a mind of its own. When I open the driver door with the key it immediately locks again. This will happen over and over again. If I turn the key counter clockwise and hold it to the left I can feel it trying to lock again, but it stays open. A couple of times this week I came out to the garage and the doors had locked on their own. Also, once in a while, they will lock while driving down the road. I have taken it to the local sportscar mechanics, but he scratches his head. I took it to the BMW folks in Minneapolis...and, of course, it wouldn't do it for them...so they offered no solution. Any thoughts or suggestions who to talk to about this perplexing problem?

Go under the rear seat, drivers side, to the rear power distribution box box and check the fuses. I believe numbers 30 and 31, and check for a blown fuse.

Try the trunk lock actuator. I replaced one with the opposite symptoms. You would lock vehicle with key or remote and because of bad trunk lock actuator, it told the car that the trunk was not locked, and thus went and unlocked the rest of the doors based on that one signal. Try unplugging the trunk lock actuator to take it out of the picture and see if it works.

Do not remeber if I sent you this, but, close all doors,trunk. and sunroof. With the key, lock the passeenger side door, rotate key to about 110 degrees and you will hear the trunk lock clunk. Remove key and go to drivers door and unlock with the key,. Thewse cars get their cnetral locking out of synchronization from time to time and the procedure i send here is how to resynchronize. My bimmer woild just po the locks as I drove down the road, I could reach over and re lock and all was fine, but by re-synchronizing all is now well. This is the preferred method to lifting the rear seat cushion, especially if you have power rear seats.