See also:

Switch off the engine during longer stops
Switch off the engine during longer stops, e.g., at traffic lights, railroad crossings or in traffic congestion. Fuel savings are achieved after the vehicle is switched off for only approx. 4 s ...

BMW Assist or ConnectedDrive
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Using the door lock
General information Locking from the outside Do not lock the vehicle from the outside if there are people in it, as the vehicle cannot be unlocked from inside without special knowledge.◀ ...