2010 Jeep Grand Cherokee Owner's Manual - Page 310

STARTING AND OPERATING 309 Tire Pressure Monitoring Telltale Light as long as none of the road tires are below the low pressure warning threshold. • 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 switch cycle, a chime will sound, a "TIRE LOW PRESSURE" message will be displayed in the instrument cluster for 60 seconds, and the Tire Pressure Monitoring Telltale Light will turn ON. After driving the vehicle for up to 20 minutes above 15 mph (25 km/h), the Tire Pressure Monitoring Telltale Light will flash on and off for 75 seconds and then remain on solid. In addition, a "CHECK TPM SYSTEM" message will be displayed for 75 seconds. For each subsequent ignition switch cycle, a chime will sound, a "CHECK TPM SYSTEM" message will be displayed for 75 seconds, and the Tire Pressure Monitoring Telltale Light will flash on and off for 75 seconds and then remain on solid. 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 and the Tire Pressure Monitoring Telltale Light will turn OFF, as long as no tire pressure is below the low-pressure warning limit in any of the four active road tires. The vehicle may need to be driven for up to 20 minutes above 15 mph (24 km/h) in order for the TPMS to receive this information. Premium System - If Equipped The Tire Pressure Monitor System (TPMS) uses wireless technology with wheel rim-mounted electronic sensors to monitor tire pressure levels. Sensors, mounted to each wheel as part of the valve stem, transmit tire pressure readings to the Receiver Module. 5