Description And Operation: Description: Operation
Each time the vehicle is driven, the TPMS learns the locations of the following four wheel-mounted sensors by combining Radio Frequency (RF) transmissions with data from the ABS module:
- FL (front left)
- FR (front right)
- RL (rear left)
- RR (rear right)
The system enters Parking mode after the vehicle speed has been less than 12.5 mph (20 km/h) for 15 minutes. In Parking mode, the tire pressure sensors transmit a coded signal to the TPM module once every 13 hours. If the tire pressure decreases by more than 7kPa (1 PSI; 0.07 bar), the sensor transmits more often to show that the tire pressure is reducing.
The process of locating the sensors is known as 'Auto Location' and takes up to 10 minutes to complete. During this period, the tire sensors transmit at regular intervals, that is, once every 15 seconds, while the vehicle speed is above 12.5 mph (20 km/h). For the remainder of the drive cycle, the tire sensors transmit once every 60 seconds while the vehicle speed is above 12.5 mph (20 km/h) or, if a change in tire pressure is sensed, until the vehicle stops or the vehicle speed is less than 12.5 mph (20 km/h) for 15 minutes and the system returns to Parking mode.
At 25% deflation (or 20% for the EU market), the amber warning indicator in the IC comes on and an appropriate message and/or graphic appears in the message center.