2008 Mercedes S-Class Owner's Manual - Page 564

Operation Tires and wheels Reactivating Advanced TPMS The TPMS must be reactivated when you have adjusted the tire inflation pressure to a new level (e.g. because of different load or driving conditions). The TPMS is then recalibrated to the current tire inflation pressures. Warning! Under-inflation also reduces fuel efficiency and tire tread life, and may effect the vehicle's handling and stopping ability. Please note that the TPMS is not a substitute for proper tire maintenance, and it is the driver's responsibility to maintain correct tire pressure, even if under-inflation has not reached the level to trigger illumination of the TPMS low tire pressure telltale. USA only: Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when the system is not operating properly. The TPMS malfunction indicator is combined with the low tire pressure telltale. When the system detects a malfunction, the telltale will flash for approximately one minute and then remain continuously illuminated. This sequence will continue upon subsequent vehicle start-ups as long as the malfunction exists. When the malfunction indicator is illuminated, the system may not be able to detect or signal low tire pressure as intended. TPMS malfunctions may occur for a variety of reasons, including the installation of replacement or alternate tires or wheels on the vehicle that prevent the TPMS from functioning properly. Always check the TPMS malfunction telltale after replacing one or more tires or wheels on your vehicle to ensure that the replacement or alternate tires and wheels allow the TPMS to continue to function properly. G i If a condition causing the TPMS to malfunction develops, it may take up to 10 minutes for the system to signal a malfunction using the TPMS telltale flashing and illumination sequence. The telltale extinguishes after a few minutes driving if the malfunction has been corrected. It is the driver's responsibility to calibrate the TPMS on the recommended cold inflation pressure. Underinflated tires affect the ability to steer or brake the vehicle. You might lose control over the vehicle. i Operating radio transmission equipment (e.g. wireless headsets, two-way radios) in or near the vehicle could cause the TPMS to malfunction. Using the tire Tire and Loading Information placard on the driver's door B-pillar ( page 553) or, if available, the supplemental tire inflation pressure information on the inside of the fuel filler flap ( page 538), make sure the tire inflation pressure of all four tires is correct. 563