FORD 2002 F-550 v.1 - Manual (Page 157)

The reverse sensing system is
automatically enabled when the gear
selector is placed in R (Reverse)
and the ignition is ON. A reverse
sensing control allows the driver to
disable the reverse sensing system only when the ignition is ON, and the
gear selector is in R (Reverse).
The OFF indicator remains illuminated when the system is disabled. The
system defaults to ON every time the reverse gear is selected. Press the
control to disable or enable the system.
The indicator will remain illuminated to indicate a failure of the reverse
sensing system.
The reverse sensing system may have reduced performance or an
increased chance of false detection if the tailgate is not locked in the
vertical position. When the tailgate is down, the driver may experience a
continuous or intermittent tone. This also applies if items being hauled in
the box do not fit entirely inside and protrude rearward.
Always keep the sensors (located on the rear bumper/fascia) free
from dirt, snow and ice (do not clean the sensors with sharp
objects). These elements may cause the system to operate
inaccurately.
If the vehicle sustains damage to the rear bumper/fascia, leaving
it misaligned or bent, the sensing zone may be altered causing
inaccurate measurement of obstacles or false alarms.
FOUR-WHEEL DRIVE (4WD) OPERATION (IF EQUIPPED)
For important information regarding safe operation of this type
of vehicle, see Preparing to drive your vehicle in this chapter.
When four–wheel drive (4WD) is engaged, power is supplied to all four
wheels through a transfer case. 4WD power can be selected when
additional driving power is desired.
OFF
Driving
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