In September 2007, Tire Pressure Monitoring Systems, commonly known as TPM systems, were required to beinstalled on all automobiles and light trucks manufactured after that date. The majority of these systems use a "direct" system. This system uses wheel based transmitters or sensors (typically incorporated into the valve stem.) The sensor reports tire pressure (and other important information) to the engine control module (ECM) or some specific controller module on the vehicle. Each time that you replace or rotate tires / wheels (or if a defective sensor is replaced) the TPM sensors must be retrained or reprogrammed in order to properly inform the driver of the correct vehicle location for a low or high pressure tire. If the receivers are not reprogrammed, the system will continue to report information but the information may be incorrect such as: correct tire pressure but wrong position on the vehicle information console or instrument cluster. What makes the OTC TPMS Tool Kit so unique is that it has been designed to trigger ALL known magnetic and frequency triggered tire sensors that have been installed at the factory by original equipment manufacturers
