I have a 1990 300D with 120K. When I put down the door lock from inside the car,on the drivers door, all the doors lock but will not open for about 40 secs. There is a hum from the right rear door, and none of the doors can be opened from the inside till the hum stops. Then they can be opened, and all the door locks open when the drivers door is opened. I have a hunch it is something to do with the vaccuum system...but please help as it is a very dangerous situation not to be able to get out of the car for this time that the locks inoperable.
Thanks for any advice......RSL007