2002 Buick Rendezvous Owner's Manual - Page 218

How the System Works If the rear park aid disable switch is not on, the rear parking assist will turn on automatically when the shift lever is moved into REVERSE (R) and the vehicle speed is less then 3 mph (5 km/h). When the system turns on, the three lights on the display will illuminate for 1.5 seconds to let you know that the system is working. The red light will flash to indicate that the system is disabled if your vehicle is moving in REVERSE (R) at a speed greater then 3 mph (5 km/h). When shifting into REVERSE (R) with the vehicle speed less than 3 mph (5 km/h) and an object is detected, one of the following will occur: A chime will sound the first time an object is detected, if the object is between 20 inches (0.5 m) and 5 feet (1.5 m) away. RPA can detect objects 3 inches (7.6 cm) and wider, and at least 10 inches (2.5 cm) tall, but cannot detect objects that are above liftgate level. In order for the rear sensors to recognize an object, it must be within operating range. 2-126