Jeep Grand Cherokee 2013 Owner's Manual page 541

If the ignition switch 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 TPM SYSTEM
message will not be present, and a pressure value will be
displayed instead of dashes. A system fault can occur by
any of the following:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the
TPM sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.
3. Lots of snow or ice around the wheels or wheel
housings.
4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
The EVIC will also display a SERVICE TPM SYSTEM
message for a minimum of five seconds when a system
fault is detected possibly related to an incorrect sensor
location fault. In this case, the SERVICE TPM SYSTEM
message is then followed by a graphic display, with
pressure values still shown. This indicates the pressure
values are still being received from the TPM Sensors but
they may not be located in the correct vehicle position.
However, the system still needs to be serviced as long as
the SERVICE TPM SYSTEM message exists.
NOTE: There is no tire pressure monitoring sensor in the
spare tire. The TPMS will not be able to monitor the tire
pressure. If you install the spare tire in place of a road tire
that has a pressure below the low-pressure warning limit,
upon the next ignition switch cycle, the Tire Pressure
Monitoring Telltale Light will remain ON, a chime will
sound, and the EVIC will still display a "flashing"
pressure value in the graphic display and an Inflate to
XXX kPa message will be displayed. After driving the
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