hi.. i really need help my 93 mercedes 300se drivers door lock wont work with the key. it turns freely lock or unlock but locks from the inside and the alarm green and red light also not working with the key. but works with the remote what can this be, kinda sound like a cable come loose are something what do you guys think, are where do i start first i really appreciate your help thanks alot.

i fix it thanks for your help.

I have the same issue on a 95 C280. Key turns freely in the drivers side lock but doesn't lock or unlock the door. Passenger side works fine. What did you do to fix he problem?

how is going... on my car what happen was the little pin on the door lock cylinder come off. so what you have to do is remove the outside handle and you will see what happen clearly. its very eazy you dont even have to remove the inside door panel at all. it can be fix from the outside. on my car its a little bolt on the door jam with a black plastic cover i dont know about your car mabe the same have fun.