Tire Pressure Control (RDC Tire Pressure Check or DDS Deflation Detection System)

Tire Pressure Control (RDC)

Introduction
The task of the tire pressure control system is to remind the driver in good time to check the tire pressure as it decreases and to warn him in the event of a flat tire. The RDC system therefore enhances vehicle safety and convenience for the driver. Nevertheless, decision priority and responsibility remain with the driver.

Advantages:
- Increased driving safety by early warning in the event of rapid pressure loss
- Tire damage caused by excessive flexing in conjunction with low tire pressure is avoided
- Deviations from set tire pressure are monitored
- Slow pressure loss is recognized in good time

Components:
- Control module for signal evaluation
- One receive antenna per wheelhouse
- Wheel electronics with valve
- Initialization button

Messages to driver
Soft warning: This operating status is characterized by a minimum tire pressure (0.2 bar under set pressure) at which driving safety is still ensured. The driver is requested via the check control to correct the pressure.

Hard warning: Driving safety is no longer ensured, the driver is requested to check the tires immediately.

A hard warning is active when the pressure loss drops either 0.4 bar or 16% below the set pressure value or drops below a value stored in the control module.

IMPORTANT: Initialization must always be carried out after every tire pressure correction. for this purpose, the initialization button is pressed (min. 6 seconds) with the ignition switched on until the "tire pressure set" appears in the check control. After several minutes driving time during which the system carries out wheel identification and a plausibility check, the RDC adopts this tire pressure as the set point to be monitored.

IMPORTANT: The following display texts can appear in the check control: Tire pressure set, tire monitoring inactive, check tire pressure, tire failure, tire failure front right, tire failure front left, tire failure rear right, tire failure rear left

System description
The wheel electronic units are mounted within the tires and measure the tire pressure as well as the tire temperature. The measured data are sent from the wheel via an output stage in the wheel electronic unit. The power is supplied by a lithium battery in the wheel electronics. Each electronic control module features its own code which is also sent during each data transfer.

The data sent by the wheel electronic units are received via antennas mounted in the wheelhouse and transferred via shielded cables to the control module.

As part of the wheel identification procedure, the system automatically learns what wheel electronic units belong to the vehicle. This function ensures that data from another vehicle cannot be evaluated.