2011 Chevrolet Volt Owner's Manual - Page 346

9-44 Driving and Operating High-toned beeps from the front speakers are for objects detected near the front bumper. Low-toned beeps from the rear speakers are for objects detected near the rear bumper. The interval between the beeps becomes shorter as the vehicle gets closer to the obstacle. When the distance is less than 30 cm (12 in) the beeps are continuous. To be detected, objects must be at least 25.4 cm (10 in) off the ground and below hood or hatch level. Objects must also be within 1.2 m (4 ft) in front of the vehicle and 2.5 m (8 ft) from the rear bumper. This distance may be less during warmer or humid weather. PARK ASSIST OFF displays on the Driver Information Center (DIC) to indicate that UFRPA is off. The message disappears after a short period of time. Objects Detected by Both the Front and Rear Sensors If objects are detected at the same time near both the front and rear bumpers while backing up, the beeps only sound to indicate that objects are close to the rear bumper. If an object comes within 0.3 m (1 ft) of the front bumper while the vehicle is backing up and at the same time there is another object further than 0.3 m (1 ft) from the rear bumper, then the beeps only sound to indicate the object that is closer to the front bumper. How the System Works UFRPA comes on automatically when the shift lever is moved into R (Reverse). The front and rear sensors are automatically turned on. After the vehicle is shifted out of R (Reverse), the rear sensors are turned off and the front sensors stay on until the vehicle is above a speed of 8 km/h (5 mph). The front sensors may also be turned on by pressing the park assist button in the overhead console without shifting into R (Reverse) while the vehicle is traveling at a low speed. See "Turning the System On and Off" later in this section. When the vehicle is in N (Neutral), the system may be active. If the vehicle is in a car wash, the sensors may detect objects in the car wash. See "Turning the System On and Off" later in this section to turn the system off.