Cadillac 2005 DeVille Owner's Manual page 143

How the System Works
URPA comes on automatically when the shift lever is
moved into REVERSE (R). When the system comes on,
the three lights on the display will briefly illuminate to
let you know that the system is working. If your vehicle is
moving in REVERSE (R) at a speed greater than
3 mph (5 km/h), the red light will flash to remind you the
system does not work at this speed.
The URPA display is
located inside the vehicle,
above the rear window.
It has three color-coded
lights that can be seen
through the rearview mirror
or by turning around.
The first time an object is detected while in
REVERSE (R), a chime will sound and the following
will occur in sequence, depending on the distance from
the object:
•
At 5 feet (1.5 m) a chime will sound and one amber
light will be lit;
•
at 40 inches (1.0 m) both amber lights will be lit;
•
at 20 inches (0.5 m) a continuous chime will sound
and all three lights (amber/amber/red) will be lit; and
•
at 1 foot (0.3 m) a continuous chime will sound and
all three lights (amber/amber/red) will flash.
URPA can detect objects 3 inches (7.6 cm) and wider,
and at least 10 inches (25.4 cm) tall, but it cannot detect
objects that are above trunk level. In order for the
rear sensors to recognize an object, it must be within
operating range.
If the URPA system is not functioning properly, the
display will flash red, indicating that there is a problem.
The light will also flash red while driving if a trailer is
attached to your vehicle, or a bicycle or object is on the
back of, or hanging out of your trunk. The light will
continue to flash until the trailer or the object is removed
and your vehicle is driven forward at least
15 mph (25 km/h).
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