2009 Buick Lucerne Owner's Manual - Page 123

How the System Works URPA comes on automatically when the shift lever is moved into R (Reverse). The rear display briefly illuminates to indicate the system is working. URPA operates only at speeds less than 5 mph (8 km/h). If the vehicle is above this speed, the red light on the rear display will flash. To be detected, objects must be at least 10 inches (25.4 cm) off the ground and below trunk level. Objects must also be within 8 feet (2.5 m) from the rear bumper. This distance may be less during warmer or humid weather. A single beep will sound the first time an object is detected between 23 inches (0.5 m) and 8 feet (2.6 m) away. Beeping will occur for a short time when the vehicle is closer than 1 foot (0.3 m) from the object. The following describes what will occur with the URPA display as the vehicle gets closer to a detected object: Description amber light amber/amber lights amber/amber/red lights amber/amber/red lights flashing and beep for five seconds English 8 ft 40 in 23 in 1 ft Metric 2.5 m 1.0 m 0.6 m 0.3 m The system can be disabled through the Driver Information Center (DIC). See "Park Assist" under DIC Operation and Displays on page 3-52 for more information. 2-39