Opening the trunk hands-free
If your hands are full and you have your key with you, just pass your foot under the rear bumper once.
If you have your hands full, such as when carrying bags, it can be useful for the trunk to open automatically.
Opening the trunk this way does not unlock the other doors.

Make sure you have a distance-capable key on you.
Make a single, slow kicking motion under the rear bumper and step back.
A short sound signal indicates that the trunk lid is about to open.
Note
Repeated foot movements cancel or reset the activation.
When you want to use the hands-free feature for closing the trunk, repeat the kicking motion once.
A short audible signal indicates that the trunk lid is about to close.
If the function appears to be unresponsive, keep in mind that obstructions to the sensor such as mud can interfere with a proper response.
Any attachments on the rear of the vehicle, such as a bicycle rack, may also interfere with the sensor.