2009 Chrysler Aspen Owner Manual - Page 331

STARTING AND OPERATING 329 For example, your vehicle has a recommended cold (parked for more than three hours) placard pressure of 33 psi (227 kPa). If the ambient temperature is 68°F (20°C) and the measured tire pressure is 28 psi (193 kPa), a temperature drop to 20°F (-7°C) will decrease the tire pressure to approximately 24 psi (165 kPa). This tire pressure is sufficiently low enough to turn on the TPMS light. Driving the vehicle may cause the tire pressure to rise to approximately 28 psi (193 kPa), but the TPMS light will still be ON. In this situation, the TPMS light will turn off only after the tires have been inflated to the vehicle's recommended cold placard pressure value. CAUTION! The TPMS has been optimized for the original equipment tires and wheels. TPMS pressures have been established for the tire size equipped on your vehicle. Undesirable system operation or sensor damage may result when using replacement equipment that is not of the same size, type, and/or style. Aftermarket wheels can cause sensor damage. Do not use aftermarket tire sealants or balance beads if your vehicle is equipped with a TPMS, as damage to the sensors may result. 5 CAUTION! After inspecting or adjusting the tire pressure always reinstall the valve stem cap. This will prevent moisture and dirt from entering the valve stem, which could damage the tire pressure monitoring sensor.