FORD 2011 Flex v.2 - Manual (Page 273)

WARNING: This system is not designed to prevent contact with
small or moving objects. The system is designed to provide a
warning to assist the driver in detecting large stationary objects to
avoid damaging the vehicle. The system may not detect smaller
objects, particularly those close to the ground.
WARNING: Certain add-on devices such as large trailer hitches,
bike or surfboard racks and any device that may block the
normal detection zone of the RSS system may create false beeps.
The RSS detects obstacles up to six
feet (two meters) from the rear
bumper with a decreased coverage
area at the outer corners of the
bumper, (refer to the figures for
approximate zone coverage areas).
As you move closer to the obstacle,
the rate of the tone increases. When
the obstacle is less than 10 inches
(25.0 cm) away, the tone will sound
continuously. If the RSS detects a
stationary or receding object further
than 10 inches (25.0 cm) from the
side of the vehicle, the tone will
sound for only three seconds. Once
the system detects an object
approaching, the tone will sound
again.
While receiving a warning the radio volume will be reduced to a
predetermined level. After the warning goes away, the radio will return
to the previous value.
The RSS automatically turns on when the gearshift lever is placed in R
(Reverse) and the ignition is on. A control in the message center allows
the driver to disable the system, refer to Message center in the
Instrument Cluster chapter for more information.
Note: If the system cannot be turned off, refer to MyKey™ in the Locks
and Security chapter for more information.
Driving
273
2011 Flex (471)
Owners Guide, 2nd Printing
USA (fus)