On the E 53 as you have figured out, the inside door handles are disabled when locked.

To defeat this, for example your wife locked you in the car and left, you need to hold down the creek lock button while pulling the door handle twice.

This will trip the alarm so that's what happens. You'd retrieve key as fast as you can and disable the alarm.

Picking the lock will work. All mechanical access is disabled at the lock/latch. The levers are simply disconnected when double locked.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)