Ford 2013 Explorer Owner's Manual page 264

264
System Sensors
WARNING: Just prior to the system recognizing a blocked
condition and alerting the driver, the number of missed objects
will increase. To help avoid injuries, NEVER use the BLIS as a
replacement for using the side and rear view mirrors and looking over
your shoulder before changing lanes. BLIS is not a replacement for
careful driving and only an assist.
Note: It is possible to get a blockage warning with no blockage present;
this is rare and known as a false blockage warning. A false blocked
condition either self-corrects or clears after a key cycle.
If the system detects a degraded performance condition, BLIND SPOT
NOT AVAILABLE, or CROSS TRAFFIC NOT AVAILABLE appear in
the information display and the alert indicator illuminates in the
appropriate mirror(s). The information display warning can be cleared
but the alert indicator remains illuminated.
When the blockage is removed, the system can be reset in two ways: 1)
when at least two objects are detected while driving, or 2) turn the
ignition key from on to off, then back on. If the blockage is still present
after the key cycle, the system senses again that it is blocked after
driving in traffic.
Reasons for messages being displayed
The radar surface is
dirty or obstructed
The radar surface is
not dirty or obstructed
2013 Explorer (exp)
Owners Guide gf, 2nd Printing
USA (fus)
Driving Aids
The system uses radar sensors
which are located behind the
bumper fascia on each side of the
vehicle. Do not allow these areas to
become obstructed by mud, snow or
bumper stickers, as this can cause
degraded system performance.
Clean the fascia area in front of the radar or
remove the obstruction.
Drive normally in traffic for a few minutes to
allow the radar to detect passing vehicles so it
can clear the blocked state.