Low Pressure Monitoring

The tire pressure sensor transmits data by RF (433 MHz) signal. These signals contain data which corresponds to sensor identification, tire pressure, tire temperature, acceleration and sensor mode.

In parking mode the tire pressure sensors transmit a coded signal to the TPMSCM once every 13 hours. If the tire pressure decreases by more than 0.06 bar (1 PSI) the tire pressure sensor will transmit more often as pressure is lost.

As each tire pressure sensor identification is learnt and auto-located by the TPMSCM, it is assigned a position on the vehicle and is monitored for the remainder of that drive cycle in that position.

This process is known as 'Auto Location' and takes up to 10 minutes (less if the tire pressure sensor positions are already known in the TPMSCM)

During this period the tire pressure sensors transmit at regular intervals once every 16 seconds.

For the remainder of the drive cycle the tire pressure sensors transmit once every 60 seconds or if a change in tire pressure is sensed until the vehicle stops and the tire pressure monitoring system returns to parking mode.

Once the wheel position is established, the auto-location function does not start again until the vehicle has been parked for more than 15 minutes. The signal transmissions from each tire pressure sensor continue at one minute intervals whilst the vehicle is being driven above 20kph. This transmission is to monitor the tire pressure. The warning occurs at 25% for NAS (20% for EU markets) deflation below the recommended pressure and comprises the low tire pressure warning indicator and an appropriate message displayed in the IC message center. The message center will also display additional information about the position of the affected wheel(s).