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. 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 the vehicle is stationary the sensors go into a stationary mode. In this mode the sensors sample tire pressure once every 20 seconds and transmit in stationary mode once every 60 minutes. As vehicle speed increases, centrifugal force closes the sensors internal roll switches causing the sensors to go into drive mode. In this mode, the sensors sample tire pressure once every 30 seconds and transmits in drive mode once every 60 seconds. The PDM receives and translates the data contained in each sensor RF transmission into sensor presence, sensor mode and tire pressure. The sensors compare their current pressure sample with their last transmitted pressure and will transmit in re-measure mode whenever an 11 kPa (1.6 psi) change in tire pressure has occurred.

When 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. Both the DIC message and the IPC indicator can be cleared by adjusting tire pressures to the recommended kPa/psi. Refer to Label - Vehicle Certification (w/o RPO Z49) or Label - Vehicle Certification (w/RPO Z49) in General Information. 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 sensors pressure range is 0-351 kPa (0-51 psi). The sensors pressure accuracy from -10 to +70° C (+14 to +158° F) is plus or minus 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 the following:

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