Door lock issues

[JD8706]

Hello, I just recently purchased a 2008 BMW X3 3.0SI and I love it. I do have one issue however that is perplexing. My drivers door will not physically unlock with the key. The central lock/unlock button works for all the doors, the lock and unlock buttons on the keyfob work fine on all the doors and the interior drivers door handle unlocks the door when I pull it. I just cannot unlock the door by physically putting the key in the lock and turning it. I checked the door lock fuses and they're all fine. Any ideas? The only reason I really want to solve this is I don't want to be stranded somewhere if my keyfob happens to die and I can't get back into my car. Any help is appreciated to avoid a potentially expensive trip to the dealership.

Thank you!

[jclausen]

The door lock tumbler is probably connected to the latch via a rod that is part of the tumbler. When the door is open you might see there small oval rubber plugs that are on the same plane as the outer handle. If your remove the little cover there might be a torx screw that when loosened would allow you to pull the tumbler out to inspect the part that engages the latch, if it was broken then the tumbler would have to be replaced, which comes from the dealer and is coded for your key