Tire Pressure Monitor

TIRE PRESSURE MONITOR DESCRIPTION AND OPERATION
The Tire Pressure Monitor (TPM) system warns the driver when a significant loss of tire pressure occurs in any of the 4 tires while the vehicle is being driven. The system uses the Passenger Door Module (PDM), Body Control Module (BCM), Driver Information Center (DIC), Instrument Panel Cluster (IPC), a radio frequency (RF) transmitting pressure sensor inside each wheel/tire assembly, and the serial data circuit to perform the system functions. When vehicle speed is less than 32 km/h (20 mph), the sensors go into stationary mode. In this mode the sensors transmit once every 60 minutes to minimize sensor battery consumption. As vehicle speed increases to above 32 km/h (20 mph)centrifugal force closes the sensor's internal roll switch causing the sensors to go into drive mode. In this mode, the sensor transmits once every 60 seconds to the PDM. The PDM translates the information within this RF transmission into sensor presence, sensor mode and tire pressure. If the TPM system detects a significant loss of tire pressure. the CHECK TIRE PRESSURE warning message is displayed on the DIC and the low tire pressure warning indicator is displayed on the IPC, which appears as a cross section of a tire with an exclamation mark inside. Both the DIC message and the IPC indicator can be cleared by adjusting tire pressures to the recommended kPa/psi. The system does not display the individual tire pressures, or their location on the DIC, nor will it indicate which tire pressure is low. The sensor's pressure accuracy from -10 to +70 °C (+14 to +158 °F) is ± 7 kPa (1 psi). The PDM has the ability to detect malfunctions within the TPM system. Any malfunctions detected will cause the DIC to display the SERVICE TIRE MONITOR warning message. For more information on other functions of the PDM, refer to Keyless Entry System Description and Operation, Power Windows Description and Operation, and to Power Door Locks Description and Operation.