Jeep Grand Cherokee SRT8 2012 Owner's Manual page 435

NOTE: Your system can be set to display pressure units
in PSI, kPa, or BAR.
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
STARTING AND OPERATING 433
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 the trigger compo-
nent an incorrect sensor location fault. In this case, the
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