Hi. I have a 2015 DS3. When put into reverse the sensor panel comes up on the dash as if ur right up against something (ie green, yellow & red light and the ! Symbol). It’s on the central area only. When u pass by the back of the car the 2 outer panels light up ok. When u cover (lightly touch) any of the central rear sensors the dasch comes up with a message about the system being faulty. Any ideas?