Buick 2004 Rendezvous - Manual (Page 166)

How the System Works
Unless disabled, the URPA will turn on automatically
when the shift lever is moved into REVERSE (R). When
the system turns on, the three lights on the display
will illuminate for one and a half seconds 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 that the system
does not work at speed greater than 3 mph (5 km/h).
If an object is detected at a REVERSE (R) speed of less
than 3 mph (5 km/h), one of the following will occur:
Description English Metric
amber light 5 ft. 1,5 m
amber/amber lights 40 in. 1,0 m
amber/amber/red lights &
continuous chime
20 in. 0,5 m
amber/amber/red lights
flashing & continuous
chime
1 ft 0,3 m
A chime will sound the first time an object is detected
between 20 inches (0.5 m) and 5 feet (1.5 m) away.
URPA cannot detect objects that are above liftgate level.
In order for the rear sensors to recognize an object, it
must be within detection range behind the vehicle.
When the System Does Not Seem to Work
Properly
The light may flash red when the vehicle is in
REVERSE (R) if the ultrasonic sensors are not kept
clean. So be sure to keep your rear bumper free of mud,
dirt, snow, ice, and slush. Other conditions that may
affect system performance include things like the
vibrations from a jackhammer or the compression of air
brakes on a very large truck. If after cleaning the
rear bumper and then driving forward at least 15 mph
(25 km/h), the display continues to flash red, see
your dealer.
If a trailer was attached to your vehicle, or a bicycle or
an object was on the back of, or hanging out of your
liftgate during your last drive cycle, the light may
also flash red. The light will continue to flash whenever
in REVERSE (R) until your vehicle is driven forward
at least 15 mph (25 km/h) without any obstructions
behind the vehicle.
For cleaning instructions, see Cleaning the Outside of
Your Vehicle on page 5-103.
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