See also:

The concept
The central locking system becomes active when the driver's door is closed. The system simultaneously engages and releases the locks on the following: ▷ Doors. ▷ Trunk lid. ▷ ...

Enabling operation in the rear
Only possible via the iDrive in the front. 1. "Settings" 2. "Allow rear control" 3. Select the desired priority. ...

In the glove compartment
Push the handle up, arrow 1, and open the lid, arrow 2. ...