When Inflating Your Tires; How Temperature Affects Your Tire Pressure - Ford 2012 Mustang Owner's Manual

Tires, Wheels and Loading
Low tire
pressure
warning light
Flashing warning
light

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 (TPMS) 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 TPMS as being significantly lower
than the recommended inflation pressure and activate the TPMS 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.
190
2012 05+ Mustang (197)
Owners Guide, 1st Printing
USA (fus)
Possible Customer action required
cause
Spare tire in Your temporary spare tire is in
use 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.
TPMS If your tires are properly inflated
malfunction and your spare tire is not in use
and the TPMS warning light still
flashes, contact your authorized
dealer as soon as possible.