GMC 2010 Sierra - Manual (Page 202)

Object Detection Systems
Ultrasonic Rear Parking
Assist (URPA)
For vehicles with the Ultrasonic Rear Parking Assist
(URPA) system, it operates at speeds less than 8 km/h
(5 mph), and assists the driver with parking and
avoiding objects while in R (Reverse). The sensors on
the rear bumper are used to detect the distance to an
object up to 2.5 m (8 ft) behind the vehicle, and at least
25.4 cm (10 in) off the ground.
{ WARNING:
The Ultrasonic Rear Parking Assist (URPA)
system does not replace driver vision. It cannot
detect:
. Objects that are below the bumper,
underneath the vehicle, or if they are too close
or far from the vehicle
. Children, pedestrians, bicyclists, or pets.
If you do not use proper care before and while
backing; vehicle damage, injury, or death could
occur. Even with URPA, always check behind the
vehicle before backing up. While backing, be sure
to look for objects and check the vehicle's mirrors.
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