Park Distance Control: Introduction
Park Distance Control is a safety/convenience system that is an option on the E46. The system is carried over from the E39 and features the ultra-sonic sensors on the rear bumper only.
The sensors detect the close proximity to other objects when maneuvering the vehicle in tight spaces (such as parallel parking or parking in narrow garages spaces).
The driver is warned, through an audible tone (beeping), when the vehicle comes close to another object. As the distance to the object decreases, the beeping frequency increases until a steady tone is produced. As the distance to the object increases, the steady tone will return to a beep and stop when the vehicle moves away from the object.
The PDC is automatically switched ON when the ignition is switched on, however it does not become active until the vehicle is shifted into reverse.