GF40.15-P-5131RI TPM (RDK) Wheel Sensor, Component Description

GF40.15-P-5131RI TPM [RDK] wheel sensor, component description
- with CODE (475) Tire pressure monitor (premium)
- with CODE (470) Tire pressure monitor (base)
- Siemens company
- refinement package
- as of model year 09

Component Identification:

Location
The TPM [RDK] wheel sensors are bolted securely to the respective rim.

Task
The TPM [RDK] wheel sensors are sensors which transmit the following data via radio signal:
- Absolute pressure
- Temperature of TPM wheel sensor
- Radial acceleration of TPM wheel sensor
- Wheel detection

These data are received via the central TPM [RDK] antenna (A2/97) and evaluated by the TPM [RDK] control unit (N88). The TPM wheel sensors contain a battery for transmitting the signals with a service life of 10 years.

The respective TPM wheel sensor must be replaced in the event of a defect in the battery.

Design
The TPM wheel sensor together with the filling valve forms a compact unit.

The following components are located in the housing:
- Pressure sensor
- Temperature sensor
- Transmitter
- Acceleration sensor (radial acceleration)
- Lithium battery for internal power supply

Function
Each TPM [RDK] wheel sensor transmits a data protocol to the central TPM [RDK] antenna. An identification number unique to the electronics is stored in each TPM wheel sensor. The TPM [RDK] control unit assigns (after a learning phase) the identification number to the wheels fitted to the vehicle. A mounted, full-size spare tire with TPM wheel sensor is detected and managed after driving for a few minutes. Following a wheel change or after replacing a TPM wheel sensor the new TPM wheel sensor with new identification number (e.g. after fitting a spare tire) is detected as quickly as possible and monitored as new identification number, even if the TPM [RDK] control unit is still receiving the previously used wheel identification numbers. Wheel identification numbers not received from the vehicle do not cause an erroneous warning.

The TPM wheel sensors are identified depending on national version and transmit their data on different frequencies:
- 315 MHz: can be seen from the frequency detail and an unfilled square symbol
- 433 MHz, detectable by the frequency detail and square symbol filled with a line grating

The TPM wheel sensors transmit 3 data telegrams every t = 60 s while driving. The absolute pressure, the wheel temperature, acceleration, identification number and status information (manufacturer, frequency, pressure range etc.) are transmitted in these data packages.

The measuring range of the TPM [RDK] wheel sensor is between p=0 and 5.5 bar (relative pressure).