Open Back Lift Gate when standing for 5 seconds with key
Tanner
The rear camera is right there, you could also do some gesture to the camera, wave, kick, whatever
Daniel Cavalheiro
Why not also a camera check to see if you are waiting behind the lift gate waving your feet?
Trevor Mack
Other manufacturers use the rest cameras to detect a person and a key near by. Some even do some fancy patented behavior with your foot and the proximity sensors + rear backup camera.