compression ratio BUICK PARK AVENUE 2005 Owner's Manual

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 briey 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 ash to remind you the
system does not work at this speed.
The rst 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.
At 1 foot (0.3 m) a continuous chime will sound and
all three lights (amber/amber/red) will ash.
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 ash red, indicating that there is a problem.
The light will also ash 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 ash until the trailer or the object is
removed and your vehicle is driven forward at least
15 mph (25 km/h).
It may also ash red if the ultrasonic sensors are not
kept clean. So be sure to keep your rear bumper free of
mud, dirt, snow, ice and slush or materials such as
paint or the system may not work properly. If after
cleaning the rear bumper and driving forward at least
15 mph (25 km/h), the display continues to ash red, see
your GM dealer. For cleaning instructions, seeWashing
Your Vehicle on page 5-87.
It may also ash red if your vehicle is moving in
REVERSE (R) at a speed greater than 3 mph (5 km/h).
Other conditions that may affect system performance
include things like the vibrations from a jackhammer or
the compression of airbrakes on a very large truck.
As always, drivers should use care when backing up a
vehicle. Always look behind you, being sure to check
for other vehicles, obstructions and blind spots.
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