Jeep 2007 Grand Cherokee Series Owner's Manual page 178

178 UNDERSTANDING YOUR INSTRUMENT PANEL
12. Tire Pressure Monitoring Telltale Light
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended
by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If your vehicle
has tires of a different size than the size indicated on the
vehicle placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for those
tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a "Tire Pressure Monitoring Telltale
Light" when one or more of your tires is significantly
under-inflated. Accordingly, when the "Tire Pressure
Monitoring Telltale Light" illuminates, you should stop
and check your tires as soon as possible, and inflate them
to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire
failure. Under-inflation also reduces fuel efficiency and
tire tread life, and may affect the vehicle's handling and
stopping ability.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver's responsibility to
maintain correct tire pressure, even if under-inflation has
not reached the level to trigger illumination of the "Tire
Pressure Monitoring Telltale Light."
The "Tire Pressure Monitoring Telltale Light" will illumi-
nate in the instrument cluster, and an audible chime will
be activated when one or more tire pressures is low. The
"Tire Pressure Monitoring Telltale Light" will flash on
and off for 60 seconds when a system fault is detected.
The flash cycle will repeat every ten minutes or until the
fault condition is removed and reset.