2009 Mercedes R-Class Owner's Manual - Page 266

Operation Tires and wheels underinflated. There is no malfunction in the TPMS. RIf the telltale flashes for 60 seconds and then stays illuminated, the TPMS system itself is not operating properly. The TPMS only functions on wheels that are equipped with the proper electronic sensors. It monitors the tire inflation pressure, as selected by the driver, in all four tires. A warning is issued to alert you to a decrease in pressure in one or more of the tires. G Warning! The TPMS does not indicate a warning for wrongly selected inflation pressures. Always adjust tire inflation pressure according to the Tire and Loading Information placard or, if available, on the supplemental tire inflation pressure information on the inside of the fuel filler flap. The TPMS is not able to issue a warning due to a sudden dramatic loss of pressure (e.g. tire blowout caused by a foreign object). In this case bring the vehicle to a halt by carefully applying the brakes and avoiding abrupt steering maneuvers. G Warning! Each tire, including the spare (if provided), should be checked every other week when cold and inflated to the inflation pressure recommended by the vehicle manufacturer on the Tire and Loading Information placard on the driver's door B-pillar or, if available, the tire inflation pressure label on the inside of the fuel filler flap. If your vehicle has tires of a different size than the size indicated on the Tire and Loading Information placard or, if available, the tire inflation pressure label, you should determine the proper tire inflation pressure for those tires. As an added safety feature, your vehicle has been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pressure telltale when one or more of your tires are significantly underinflated. Accordingly, when the low tire pressure telltale illuminates, you should stop and check your tires as soon as possible, and inflate them to the proper pressure. Driving on a significantly underinflated tire causes the tire to overheat and can lead to tire failure. Underinflation also reduces fuel efficiency and tire tread life, and may affect 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 underinflation has not reached the level to trigger illumination of the TPMS low tire pressure telltale. 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 1 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 incompatible replacement or alternate tires or wheels on the vehicle that prevent the TPMS from functioning properly. Always check the TPMS malfunction telltale after 264