Tire Pressure Monitor System (Tpms) - Jeep Grand Cherokee WK2 Owner's Manual

JOBNAME: CHRY OM INTL (Conten PAGE: 237 SESS: 2 OUTPUT: Fri Jun 4 10:52:37 2010 SUM: 49712192
/chry_pdm/chrysler/owners/grc/og
TIRE PRESSURE MONITOR SYSTEM
(TPMS)
The Tire Pressure Monitoring System (TPMS)
will warn the driver of a low tire pressure based
on the vehicle recommended cold tire pres-
sure.
The tire pressure will vary with temperature by
about 1 psi (7 kPa) for every 12°F (–11°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 "TPM Telltale Light" and the "TIRE LOW
PRESSURE" message appears, the tire pres-
sure must be increased to the recommended
cold tire pressure in order for the "TPM Telltale
Light" and the "TIRE LOW PRESSURE" mes-
sage to be turned off. The system will automati-
cally update and the "TPM Telltale Light" and
the "TIRE LOW PRESSURE" message will turn
off 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 display
the "TPM Telltale Light" and the "TIRE LOW
PRESSURE" message. Driving the vehicle may
cause the tire pressure to rise to approximately
28 psi (193 kPa), but the "TPM Telltale Light"
and the "TIRE LOW PRESSURE" message will
still display. In this situation, the "TPM Telltale
Light" and the "TIRE LOW PRESSURE" mes-
sage 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 damage
may result when using replacement equip-
ment that is not of the same size, type,
and/or style. Aftermarket wheels can cause
sensor damage. Do not use aftermarket tire
sealants or balance beads if your vehicle is
equipped with a TPMS, as damage to the
sensors may result.
(Continued)
235