Circuit Description

The tire pressure monitor (TPM) system has 4 radio frequency (RF) transmitting pressure sensors inside each wheel/tire assembly. As vehicle speed increases to at least 32 km/h (20 mph) the sensor's internal roll switch closes which puts the sensors into drive mode. The sensors begin to transmit once every 60 seconds to the endgate module (EGM) or liftgate module (LGM) if equipped. The data within the sensors RF transmission is translated by the EGM or LGM into sensor presence, sensor mode and tire pressure. If a sensor did not go into drive mode or is not transmitting at all, the EGM or LGM will set the appropriate DTC.