Ford F-150 2018 Owner's Manual page 260

Using the System
Cross Traffic Alert turns on when you start
the engine and you shift into reverse (R).
Once shifted out of reverse (R), Cross
Traffic Alert turns off.
E142440
In this first example, the left sensor is only
partially obstructed; zone coverage to the
right is nearly maximized.
F-150 (TFC) Canada/United States of America, enUSA, Edition date: 201705, First Printing
Driving Aids
Cross Traffic Alert is designed to detect
vehicles that approach with a speed up to
37 mph (60 km/h). Coverage decreases
when the sensors are partially, mostly or
fully obstructed. Reversing slowly helps
increase the coverage area and
effectiveness.
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