Using The Rear Sensing System - Ford Super Duty Owner's Manual

The sensing system warns the driver of obstacles within a certain range
of the bumper area. The system turns on automatically whenever the
ignition is switched on.
When receiving a detection warning, the radio volume is reduced to a
predetermined level. After the warning goes away, the radio volume
returns to the previous level.

Using the Rear Sensing System

The rear sensors are only active when the transmission is in R. As the
vehicle moves closer to the obstacle, the rate of the audible warning
increases. When the obstacle is fewer than 12 inches (30 centimeters)
away, the warning sounds continuously. If a stationary or receding object
is detected farther than 12 inches (30 centimeters) from the side of the
vehicle, the tone sounds for only three seconds. Once the system detects
an object approaching, the warning sounds again.
A
The system detects certain objects while the transmission is in R:
• and moving toward a stationary object at a speed of 3 mph (5 km/h)
or less.
• but not moving, and a moving object is approaching the rear of the
vehicle at a speed of 3 mph (5 km/h) or less.
• and moving at a speed of less than 3 mph (5 km/h) and a moving
object is approaching the rear of the vehicle at a speed of less than
3 mph (5 km/h).
2013 F-250/350/450/550 (f23)
Owners Guide gf, 2nd Printing, December 2012
USA (fus)
Parking Aids
A. Coverage area of up to 6 feet
(2 meters) from the rear bumper
(with a decreased coverage area at
the outer corners of the bumper).
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