The lock button is one way. Internally it's spring loaded and only locks.

When the door won't latch it's almost always because one of the handle levers to the door lock actuator are stuck in the open position.

Example; one drop of water will freeze the mechanism; if you force it open, the ice is still there and holds the lever "unlatched" and the door will not latch until you defrost the DLA. Door handle carrier cable corrosion can cause the caller l cable to effectively shrink and cause the same symptom.

You have bumped into a similar situation where the door is latched but the lever is held up a little bit. Not enough to prevent latching but enough to prevent unlatching the door.

The usual cause for that is the inside door handle cable bound in some way. Was there work done on that door recently?

With any luck you can remove the door window switch module and get in there far enough to unhook the inner door handle. At that point you should be able to operate the door from outside.

The door lock actuator also will cause the can't open when the motor fails for double-lock but that won't give the initial symptom of won't latch.

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