2008 Jeep Grand Cherokee Owner's Manual - Page 335
2008 Jeep Grand Cherokee Manual
Page 335 highlights
STARTING AND OPERATING 335 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 none of road tires are below the low pressure warning threshold. The EVIC will also display a "Spare Low Pressure" text message, and the graphic display will show a tire pressure value in place of the flashing low tire pressure value. NOTE: If your vehicle is not equipped with a matching full size spare wheel and tire assembly, it does not have a 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 key 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. After driving the vehicle for up to 10 minutes above 15 mph (24 km/h), the "Tire Pressure Monitoring Telltale Light" will flash on and off for 75 seconds and then remain on solid. In addition, the EVIC will display a CHECK TPM SYSTEM message for 3 seconds and then display dashes (- -) in place of the pressure value. For each subsequent ignition key cycle, a chime will sound, the "Tire Pressure Monitoring Telltale Light" will flash on and off for 75 seconds and then remain on solid, and the EVIC will display a CHECK TPM SYSTEM message for 3 seconds and then display dashes (- -) in place of the pressure value. Once you repair or replace the original road tire, and reinstall it on the vehicle in place of the spare tire, the TPMS will update automatically. 5