The contact owns a 2020 Nissan Maxima. The contact stated the collision sensor system on the vehicle was malfunctioning, causing the vehicle to brake on its own while reversing in parallel parking. The contact stated the vehicle would always make buzzing sounds while parking. The contact stated while he was reversing out of a parking space on a hill, the vehicle inadvertently stopped, causing him to hit the vehicle in front of him. The dealer and the manufacturer were not notified of the failure. The vehicle was not diagnosed nor repaired. The approximate failure mileage was 25,000.