2007 Buick Rendezvous Owner's Manual - Page 198

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 amber light amber/amber lights amber/amber/red lights & continuous chime amber/amber/red lights flashing & continuous chime English 5 ft 40 in 20 in 1 ft Metric 1.5 m 1.0 m 0.5 m 0.3 m 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 Washing Your Vehicle on page 455. 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. 198