Wheel electronics
In all wheels, wheel electronics systems are installed in the wheel drop center. The wheel electronics systems are bolted onto the filling valves (made of metal). All wheel electronics systems are common parts. The valid operating temperature lies between -40 °Celsius and +125 °Celsius. The wheel electronics monitor the actual temperature in the tire. If the temperature is greater than approx. 115°C, the tire pressure control switches to a mode with restricted functionality. Under certain circumstances, the hardware is switched off. Each wheel electronics unit incorporates an acceleration sensor. The acceleration sensor recognizes whether the wheel is stationary or rotating.
When the wheels are stationary the remote receiver does not transmit messages to the Dynamic Stability Control (DSC). The wheel electronics are in their passive state. This extends the service life of the batteries in the wheel electronics.
Once the vehicle reaches 30 km/h (18 mph) the wheel electronics switch to their "standby" mode. The wheel electronics start to transmit in defined cycles.
The wheel electronics measure the tire inflation pressure and the temperature at regular periodic intervals. The remote receiver relays these monitored data from the tire to the DSC in periodic cycles.
The DSC control unit relies on the identification number that accompanies the transmissions to assign the information to individual wheels. Should the wheel assignments be lost then the learning routine will need to be performed again: see WHEEL ASSIGNMENTS .
| Item | Explanation |
|---|---|
| 1 | Wheel electronics |
| 2 | Transmission frequency |
| 3 | Pressure sensor |
| 4 | Valve |
The wheel electronics are supplied with power by a lithium ion battery. The service life is designed for approx. 10 years. The remaining service life is displayed with a resolution of 1 month accuracy.