FORD 2003 Expedition v.1 - Manual (Page 207)

To help avoid personal injury, always use caution when in
reverse and when using the RSS.
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 objects to avoid damaging the vehicle.
The system may not detect smaller objects, particularly those close to
the ground.
The system will assist the driver in detecting certain objects while the
vehicle slowly moves in reverse at speeds less than 10 km/h (6 mph).
The system is not effective at speeds greater than 10 km/h (6 mph) and
may not detect certain angular or moving objects.
The system detects obstacles up to
a maximum range of six meters (20
ft.) behind 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 distance to the
obstacle is less than 45.0 cm (18
in.), the tone will sound
continuously. If the system detects
an object that is approaching the
vehicle at such as rate that rapid
braking is required, a very high rate
tone will sound. If this tone is heard
while reversing, the driver is advised
to slow down immediately until the
tone either changes to a slower rate
or stops.
The system is automatically enabled when the gear selector is placed in
R (Reverse) and the ignition is ON. The RSS control in the message
center allows the driver to disable the system only when the ignition is
ON, and the gear selector is in R (Reverse).
Driving
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