FORD 2013 Explorer v.4 - Manual (Page 231)

USING YOUR FOUR WHEEL DRIVE (4WD) SYSTEM
The intelligent 4WD system continuously monitors vehicle conditions and
automatically adjusts the power distribution between the front and rear
wheels. It combines transparent all-surface operation with highly capable
four-wheel drive.
The 4WD system is always active and requires no driver input. It is
capable of handling all road conditions, including street and highway
driving as well as off-road and winter driving. The driver can optimize
more 4WD control by moving the terrain management switch for the
correct terrain. See the Terrain Management chapter for more
information.
Note: When an 4WD system fault is present, the warning Check 4WD
will display in the message center. The 4WD system is not functioning
correctly and will default to front-wheel drive. When this warning is
displayed, have your vehicle serviced at an authorized dealer.
Note: The 4WD Off message may also be displayed in the message
center if the 4WD system has overheated and defaulted to front-wheel
drive. This condition may occur if the vehicle was operated in extreme
conditions with excessive wheel slip, such as deep sand. To resume
normal 4WD function as soon as possible, stop the vehicle in a safe
location and stop the engine for at least 10 minutes. After the engine has
been restarted and the 4WD system has adequately cooled, the 4WD Off
message will turn off and normal 4WD function will return. The 4WD Off
message will turn off when the system cools and normal 4WD function
returns.
If your vehicle is equipped with 4WD, a spare tire of a different size
other than the tire provided should never be used. If the mini-spare tire
is installed, the 4WD system may disable automatically and enter
front-wheel drive only mode to protect driveline components. This
condition may be indicated by an 4WD Off message in the information
display. If there is an 4WD Off message in the message center from using
the spare tire, this indicator should turn off after reinstalling the repaired
or replaced normal road tire and cycling the ignition off and on. It is
recommended to reinstall the repaired or replaced road tire as soon as
possible. Major dissimilar tire sizes between the front and rear axles
could cause the 4WD system to stop functioning and default to
front-wheel drive or damage the 4WD system.
230 Four-Wheel Drive (If Equipped)
2013 Explorer (exp)
Owners Guide gf, 4th Printing, November 2012
USA (fus)