sounds like your double lock motor is on the way out.

Usually using the emergency egress method will get the double lock unlocked while it's still intermittent.

If the lock button pops up I think it's something else though as the lever that allows the unlock latch to engage is simply removed from activation when the door is double locked.

Almost sounds like a defect in the child lock mechanism. (if the door lock button pops up and outside handle will unlatch the door than that would confirm).

On numerous occasions when somebody got the doubled lock out of sync and then used the emergency egress to get it working again, it had stayed working, but I would refurbish any actuator where this happens as the only logical conclusion is the double lock motor has failed.

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