Chevrolet 2011 Volt Owner's Manual page 318

9-40 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.
Turning the System On and Off
The UFRPA system can be turned
on and off by pressing the park
assist button in the overhead
console.
The park assist button lights up
when the system is on and turns off
when it has been disabled.
When the System Does Not
Seem to Work Properly
If UFRPA does not turn on due to a
temporary condition, the message
PARK ASSIST OFF displays on the
DIC, and the light on the park assist
button turns off. This can occur
under the following conditions:
The ultrasonic sensors are not
clean. Keep the sensors free of
mud, dirt, snow, ice, and slush.
For cleaning instructions, see
Exterior Care on page 10 81.