AUXILIARY DRIVING SYSTEMS
Tire Pressure Monitor System (TPMS)
The Tire Pressure Monitoring System (TPMS) will warn the
driver of a low tire pressure based on the vehicle recom-
mended cold placard pressure.
The tire pressure will vary with temperature by about 1 psi
(7.0 kPa) for every 12°F (6.5°C). This means that when the
outside temperature decreases, the tire pressure will de-
crease. Tire pressure should always be set based on cold
inflation tire pressure. This is defined as the tire pressure
after a vehicle has not been driven for more than three
hours, or driven less than 1 mile (1.6 km) after a three-hour
period. Refer to “Tires” in “Servicing and Maintenance” 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 thresh-
old 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
placard pressure. Once the TPMS Warning Light has been
illuminated, the tire pressure must be increased to the
recommended cold placard pressure in order for the TPMS
Warning Light to be turned OFF.
NOTE:
When filling warm tires, the tire pressure may need
to be increased up to an additional 4 psi (28 kPa) above the
recommended cold placard pressure in order to turn the
TPMS Warning Light off.
The system will automatically update and the TPMS
Warning Light will extinguish once the updated tire pres-
sures 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 may have a recommended cold
(parked for more than three hours) air pressure of 35 psi
(241 kPa). If the ambient temperature is 68°F (20°C) and the
measured tire pressure is 30 psi (207 kPa), a temperature
drop to 20°F (-7°C) will decrease the tire pressure to
approximately 26 psi (179 kPa). This tire pressure is suffi-
ciently low enough to turn ON the “TPMS Warning Light.”
Driving the vehicle may cause the tire pressure to rise to
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SAFETY
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