AUXILIARY DRIVING SYSTEMS
Tire Pressure Monitoring System (TPMS)
The Tire Pressure Monitor System (TPMS) will warn the
driver of a low tire pressure based on the vehicle recom-
mended cold tire pressure.
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 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 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. The cold tire inflation pressure must not exceed the
maximum inflation pressure molded into the tire sidewall.
Refer to “Tires – General Information” in “Servicing And
Maintenace” 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 limit 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 the recommended
cold tire pressure on the placard. Once the low tire pressure
warning (Tire Pressure Monitoring System Warning Light)
illuminates, you must increase the tire pressure to the
recommended cold tire pressure in order for the Tire
Pressure Monitoring System Warning Light to turn off. The
system will automatically update and the Tire Pressure
Monitoring System Warning Light will turn off once the
system receives the updated tire pressures. The vehicle
may need to be driven for up to 20 minutes above 15 mph
(24 km/h) in order for the TPMS to receive this informa-
tion.
For example, your vehicle may have a recommended cold
(parked for more than three hours) tire pressure of 30 psi
(207 kPa). If the ambient temperature is 68°F (20°C) and the
measured tire pressure is 27 psi (186 kPa), a temperature
drop to 20°F (-7°C) will decrease the tire pressure to
approximately 23 psi (159 kPa). This tire pressure is suffi-
ciently low enough to turn on the Tire Pressure Monitoring
System Warning Light. Driving the vehicle may cause the
tire pressure to rise to approximately 27 psi (186 kPa), but
the Tire Pressure Monitoring System Warning Light will
still be on. In this situation, the Tire Pressure Monitoring
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SAFETY
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