Buick 2009 Lucerne - 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 English Metric
amber light 8 ft 2.5 m
amber/amber lights 40 in 1.0 m
amber/amber/red lights 23 in 0.6 m
amber/amber/red lights
flashing and beep for
five seconds
1 ft 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.
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