The tire pressure will vary with temperature by
about 1 psi (7 kPa) for every 12°F (6.5°C). This
means that when the outside temperature de-
creases, the tire pressure will decrease. Tire
pressure should always be set based on cold
inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven
for at least three hours, or driven less than
1 mile (1.6 km) after a three-hour period. Refer
to “Tires – General Information” in “Starting
and Operating” for information on how to
properly inflate the vehicle’s tires. The tire
pressure will also increase as the vehicle is
driven - this is normal and there should be no
adjustment for this increased pressure.
The TPMS will warn the driver of a low tire
pressure if the tire pressure falls below the low
pressure warning threshold for any reason,
including low temperature effects, or natural
pressure loss through the tire.
The TPMS will continue to warn the driver of low
tire pressure as long as the condition exists,
and will not turn off until the tire pressure is at or
above recommended cold tire pressure. Once
the low tire pressure warning has been illumi-
nated, the tire pressure must be increased to
the recommended cold tire pressure in order for
the Tire Pressure Monitoring Telltale Light to be
turned off. The system will automatically update
and the Tire Pressure Monitoring Telltale Light
will extinguish once the updated tire pressures
have been received. The vehicle may need to
be driven for up to 20 minutes above 15 mph
(24 km/h) to receive this information.
For example, your vehicle has a recommended
cold (parked for more than three hours) tire
pressure of 33 psi (227 kPa). If the ambient
temperature is 68°F (20°C) and the measured
tire pressure is 28 psi (193 kPa), a temperature
drop to 20°F (-7°C) will decrease the tire pres-
sure to approximately 24 psi (165 kPa). This tire
pressure is sufficiently low enough to turn ON
the Tire Pressure Monitoring Telltale Light. Driv-
ing the vehicle may cause the tire pressure to
rise to approximately 28 psi (193 kPa), but the
Tire Pressure Monitoring Telltale Light will still
be ON. In this situation, the Tire Pressure
Monitoring Telltale Light will turn OFF only after
the tires have been inflated to the vehicle’s
recommended cold tire pressure value.
CAUTION!
•
The TPMS has been optimized for the
original equipment tires and wheels. TPMS
pressures have been established for the
tire size equipped on your vehicle. Unde-
sirable system operation or sensor dam-
age may result when using replacement
equipment that is not of the same size,
type, and/or style. Aftermarket wheels can
cause sensor damage. Do not use after-
market tire sealants or balance beads if
your vehicle is equipped with a TPMS, as
damage to the sensors may result.
•
After inspecting or adjusting the tire pres-
sure always reinstall the valve stem cap.
This will prevent moisture and dirt from
entering the valve stem, which could dam-
age the Tire Pressure Monitoring Sensor.
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