Jeep 2007 Grand Cherokee Series Owner's Manual page 303

If the ignition key is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the "Tire Pressure Monitoring Telltale
Light" will no longer flash, the SERVICE TIRE PRESS.
SYSTEM text message will no longer display, and a
pressure value will be displayed instead of dashes.
NOTE: If your vehicle is equipped with a matching full
size spare tire, it has a tire pressure monitoring sensor,
and can be monitored by the Tire Pressure Monitoring
System (TPMS). In the event that the matching full size
spare tire is swapped with a low pressure road tire, the
next ignition key cycle will still show the "Tire Pressure
Monitoring Telltale Light" to be ON, a chime to sound, a
Low Pressure message to appear in the EVIC, and the
graphic display will still show the low tire pressure value
flashing. Driving the vehicle for up to 10 minutes above
15 mph (24 km/h) will turn OFF the "Tire Pressure
Monitoring Telltale Light" as long as the matching full
size spare tire or any other road tire(s) are not below the
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low pressure warning threshold. The EVIC will display a
"Spare Low Pressure" text message, and the graphic
display will show a new tire pressure value in place of
the flashing low tire pressure value.
NOTE: If your vehicle is equipped with a non-matching
full size spare tire, it does not have a tire pressure
monitoring sensor. Therefore, it will not be monitored by
the Tire Pressure Monitor System (TPMS). In the event
that the non-matching full size spare tire is swapped with
a low pressure road tire, every ignition key cycle will still
show the "Tire Pressure Monitoring Telltale Light" to be
ON, a chime to sound, a Low Pressure message to appear
in the EVIC, and the graphic display will still show the
low tire pressure value flashing. After the original road
tire has been properly repaired and put back onto the
vehicle in place of the non-matching full size spare tire,
the TPMS will update the graphic display on the EVIC
with a new tire pressure value instead of the flashing low
tire pressure value, and the "Tire Pressure Monitoring
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