Jeep Grand Cherokee Owner's Manual page 355

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 CHECK 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 CHECK TPM SYSTEM
message for three seconds when a system fault is de-
tected possibly related to the trigger component. In this
case, the CHECK TPM SYSTEM message is then fol-
lowed by a graphic display, with pressure values still
shown. This indicates the pressure values are still being
received from the TPM Sensors. However, the system still
needs to be serviced as long as the CHECK TPM
SYSTEM message exists.
NOTE:
• If your vehicle is equipped with a matching full-size
spare wheel and tire assembly, 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
I n f o r m a t i o n P r o v i d e d b y :
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