Door will not lock no matter what!
 

I have a drivers side door that will not lock from the inside nor the outside. It's on a 300d w123 turbo. The vac locks of course do not work either. But I just want to be able to lock it manually. Any ideas?

The door is closed when your trying to lock it correct?

I had an issue where my key wouldnt work so i would open the back door, close front and then lock it. Making sure that the passenger side would unlock with the key of course.

The door won't lock. The door-open handle on the inside is messed up a little but it still works fine. However no matter what, door open or closed I can't get the driver side door to lock. I've tried from the outside too. I can turn really hard with the key and it won't go ANYwhere. I don't know where to start to service this thing.

start here
 

Pull your door panel and start poking around. Sounds like one of the lever arms or pivot points may be jammed up.

I have high regards for the author of this: http://www.peachparts.com/Wikka/W123DoorLock

:D

#1. Don't try locking the driver door with it open. It is not designed to do that.

#2. There is a diy link for taking the door panel off if youv'e never done it. The map pocket has a tab that will break if you do it wrong.

#3. Take a look and some pics of the linkage. Post the pics here so we can better help.

There is a diaphram thing at the lock inside door panel, somewhere air is not being allowed to push one side to the other, lock is "frozen". I had a similar deal with one, I unplugged the vac lines under hood at working yellow check valve, doors lock manually. Power locks don't work. Works for me.