Door Lock (actuator) problem. See video
 

I have a problem with my drivers door where the door doesn't lock via the central locking. :(

When the button on the key fob is pushed you can here the actuator move but it goes back to it's original position (see video).

Now this obviously points towards a faulty actuator but I have now bought two second hand ones and I get the exact same response from those as I did my original one!!

Am i just incredibly unlucky and bought two actuators with the same fault as my original one or is there another cause of this problem?

Video: http://img802.imageshack.us/img802/5...ilddmozvex.mp4

Are you sure its the actuator? I'm having similar problem...my rear doors won't unlock at all with the key fob nor the central lock switch, only the front doors....my first thought would be the central lock switch so I temporarily took the switch off from my other car just to see if it works but same problem. I googled the problem and its all pointing to the GM3 which is very expensive to replace....my plan is to have it repaired, the door lock problems are usually connected with relay failures in the GM3......bmwgm5.com has all the info...you could email the guy and tell him exactly the problem he might be able to help you...

What was the issue?

I've had this issue on occasion and it ended up being the voltage reg on the alt. If the voltage drops below threshold, it will not unlock the doors. You can actually see and hear when it will happen. When you unlock when everything is normal, you can hear the actuator on the rear doors engage. When hitting the button again, it will pop the lock. But when the system is low on juice, the rear doors will not function properly. I ended up replacing my voltage reg and for months, the problem hasnt reared its head again. I confirmed the issue by doing a volt test... Whenever the problem occurred, I check the voltage and it was at 9.5 volts. After opening the door, resetting the system and locking the car again... unlock and all doors unlocked, checked voltage and it was at 12.4v. So if this is the problem you are experiencing, check the voltage.

Are you sure all the actuators are in sync with one another?

What you mean? And How woudl I check that? I dont understand your reply

the loose window swith messed with the door locking issue?

Yeap believe it or not that was the issue