When Inflating Your Tires; How Temperature Affects Your Tire Pressure - Ford Super Duty Owner's Manual

368
Low tire Possible cause
pressure
warning light
Flashing warning Spare tire in use Repair the damaged road wheel and
light
Tire pressure
monitoring
system
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.

How temperature affects your tire pressure

The tire pressure monitoring system monitors tire pressure in each
pneumatic tire. While driving in a normal manner, a typical passenger
tire inflation pressure may increase approximately 2 to 4 psi (14 to
28 kPa) from a cold start situation. If the vehicle is stationary overnight
with the outside temperature significantly lower than the daytime
temperature, the tire pressure may decrease approximately 3 psi
(21 kPa) for a drop of 30°F (17°C) in ambient temperature. This lower
pressure value may be detected by the system as being significantly
lower than the recommended inflation pressure and activate the system
warning light for low tire pressure. If the low tire pressure warning light
is on, visually check each tire to verify that no tire is flat. If one or more
tires are flat, repair as necessary. Check air pressure in the road tires.
If any tire is under-inflated, carefully drive the vehicle to the nearest
location where air can be added to the tires. Inflate all the tires to the
recommended inflation pressure.
2013 F-250/350/450/550 (f23)
Owners Guide gf, 2nd Printing, December 2012
USA (fus)
Wheels and Tires
Customer action required
tire and reinstall it on the vehicle to
restore system function. For a
description on how the system
functions, see When your temporary
spare tire is installed in this section.
If the tires are properly inflated and
the spare tire is not in use but the
light remains on, contact your
authorized dealer as soon as possible.