Passanger Rear Door Unlocking Issue

Well, the problem seems to be the passenger side (drivers) rear door interior handle. Here's my question; What would cause the mechanism to not release the door latch when you do the "double pull" on the handle? The door lock plunger rises to the unlock position, then it feels like the handle is in free play mode, like it was double locked or something it cannot be opened from the outside either. BUT, here is the catch if I cycle the central locking system once the door opens perfectly. I was thinking the door handle carrier might be the culprit, but the symptoms don't seem to match. I also checked the child lock setting to make sure it was not engaged, Before I take it to the dealer I would like to know if this is something I can fix.
Thanks in advance for the help!

I'm not 100% sure I understand your symptom.

BMW locks works a very interesting way. In short form: doors can only be unlocked in the same manner they were locked. This prevents many things like theft, and also causes some heart ache if not understood properly. Let me give an example:

1) I pull up to a retail store, get out of the car and lock with the remote. I return to the car and unlock with the physical key in the door lock cylinder. The alarm goes off. The car was not expecting to be unlocked in a manner different than it was locked.

2) I leave all my windows down on a nice warm day and lock the car with the remote. Some would-be thief sees an opportunity and reaches in to press the unlock button inside the car. The alarm should go off due to a motion sensor in the car, but even if it doesn't, the door lock button on the console inside the car does NOT unlock the car. Only the remote can unlock it in this case. This particular situation has a hazardous side effect: If you lock a person inside the car with the remote on the key, they cannot open the doors! It specifically states in the manual not to lock people in the car for this very reason.

So, if there is a problem in the central locking system, the car could be 'confused' about which state it is in and produce odd behavior like you describe. If you're lucky, there is only a small problem with that individual door. It could be the actuator that turns electrical signals from the central locking system into lock/unlock action on the door latch. It could be the central locking system itself. It could be the wiring in between them. It could be a need for grease or a chunk of debris blocking the linkage between the latch and the door handle or lock plunger. It's hard to say with the detail you've written.

My advice is to open it up and investigate. Consider it exploratory surgery

The problem is only with the one door.
It does not matter the method that is used to lock the door, manual, automatic due to speed (10 to 20 MPH) or with the remote. If you come to a stop, turn off the engine and then double pull the door handle. The first pull disengages the lock, the second opens the door. This worked on all four door up until this weekend. Now it is only working on three. To get the forth door to open I mus cycle the central lock or remote lock all the doors. Then unlock them for the forth door to open properly.

Thank you for replying and I hope that this helps you understand my problem better.

R,
Vertigow

Got it.

I've never heard of this issue before, but I'd say it's either the linkage between the internal handle and the door latch, or the child lock system acting up. I don't know how to diagnose the issue, though. It sounds like the actuator is working fine, but something along the way obviously is not.

If you can open it up and look inside the door panel (probably with a small mirror and some flashlights) maybe you can see the problem. Good luck!

I spent about an hour earliier today with the door panel off doing that very thing. I tried looking with a light and dental mirror to see if any of the linkage appears to be binding or cables frayed, but everything appears to be okay.

I also checked the child lock and both rear doors are set to be be disengaged so the door shoudl open from the inside.

This is really strange as it will open now eveytime, but only if or after I cycle the lock using the central control or remote.
Using this approach I can hear (on all four doors) an initial server action (call it a pre-unlock) then a second more agressive unlock that raises the door lock pin.

Just a frustrating situation that if you are the passanger behind the driver you are locked in as if the Child Lock is on until the locks are cycled.

Thank you again.

R,
Vertigow