Tire Pressure Sensor: Description and Operation

4432 Wheel Transmitters

The wheel transmitter is secured to the metal valve with a self-locking Torx screw in the wheel rim. The additional weight of approx. 1oz (30 grams) can be counterbalanced with wheel balancing weights.

The wheel transmitter can also be re-used in case wheel replacement becomes necessary.

The following components are integrated in the wheel transmitter:
- Transmitting antenna
- Pressure sensor
- Temperature sensor
- Measuring and control electronics
- Battery







Pressure sensor, temperature sensor as well as the measuring and control electronics are integrated into one sensor unit. Depending on the country version, two different carrier frequencies are used for radio transmission, frequencies 315 MHz and 433 MHz, the 433 MHz being assigned for the North American market. The carrier frequency is printed on the sensors, antennas and control modules. It can also be identified by the part number. The tire pressure monitoring system only functions with system components that have the identical carrier frequency.

The following data is transmitted by the wheel transmitter:
- Individual identification number (ID)
- Current tire pressure (absolute pressure)
- Current tire air temperature
- Condition of the integrated battery
- As well as the status, synchronization and control data required for safe data transmission