Audi parking system advanced with rearview camera makes parking easier. Using ultrasonic sensors to measure distance, Audi parking sysem emits an intermittent warning tone to indicate how far the car is from an obstacle. As the distance decreases, the warning tone becomes faster. It first sounds when the car is a little over 5 feet from the obstacle, becoming continuous when only 8 inches remain. Optional front Audi parking system (available only on the A8 L) can be switched off in special situations such as stop-and-go traffic. Rear Audi parking system switches on automatically when the vehicle is in reverse.