At approximately 7:00 p.m., it was already dark, and I relied on my vehicleâs rear parking-aid sensor to assist me while backing out of my driveway. However, the rear collision/parking-aid sensor did not activate and provided no audible or visual warnings. Because the sensor failed to operate, I continued reversing and unintentionally collided with a vehicle parked across the street. The malfunctioning sensor is still installed on the vehicle and is available for inspection upon request. The absence of any warning put my safety and the safety of others at risk, as I had no indication that another vehicle was behind me. There were no warning lamps, messages, or symptoms before the incident, and the failure was first noticed when the expected alert did not occur. After the accident, I contacted a Ford dealership and confirmed that the sensor had not activated at the time of the incident. I also verified afterward, in daylight conditions, that the sensor does work normally and provides warnings when objects are behind the vehicle. The issue has not yet been reproduced or inspected in person by a dealer or an independent service center, and the manufacturer has not examined the component. My insurance company has been notified of the collision.