Ford 2009 Expedition Owner's Manual page 267

Low Tire Possible
Pressure cause
Warning Light
Flashing Warning Spare tire in
Light use
TPMS
malfunction
When inflating your tires
When putting air into your tires (such as at a gas station or in your
garage), the Tire Pressure Monitoring System may not respond
immediately to the air added to your tires.
It may take up to two minutes of driving over 20 mph (32 km/h) for the
light to turn OFF after you have filled your tires to the recommended
inflation pressure.
2009 Expedition (exd)
Owners Guide, 1st Printing
USA (fus)
Tires, Wheels and Loading
Customer Action Required
Your temporary spare tire is in
use. Repair the damaged road
wheel and re-mount it on the
vehicle to restore system
functionality. For a description of
how the system functions under
these conditions, refer to When
your temporary spare tire is
installed in this section.
If your tires are properly inflated
and your spare tire is not in use
and the TPMS warning light still
flashes, have the system inspected
by your authorized dealer.
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