ELECTRONIC DAMPER CONTROL (EDC)

Electronic Damper Control (EDC) adjusts the shock absorbers, with virtually no delay, to changing road or driving conditions. It combines the best possible level of driving safety with a high degree of ride comfort or - if desired - with an especially sporty handling style.

Damper forces are constantly electronically regulated, adapting to road, load and driving conditions.
When driving on good roads, the dampers are automatically set to "soft" and provide maximum ride comfort.
When taking a bend at speed, damper forces are immediately increased automatically in the interests of extra safety. Similarly when the car suddenly passes over a bump, the system automatically switches to "medium" or "hard" and therefore ensures optimum road-holding.
There is also the option of selecting the "S" programme by means of a switch. This retains a constantly firmer, sports-style damper setting.

Your benefits :

maximum comfort and excellent road safety
individualised choice of programme between comfort and sport (two suspension settings in one)
consistently good vibration control and suspension, regardless of vehicle load

Function in detail :

All vehicle motions affecting road behaviour and driving characteristics are constantly monitored by sensors. A microprocessor evaluates all this information and passes on instructions to the dampers, where magnetic valves adjust damper force to one of the three settings.

A two-stage switch in the centre console allows the driver to choose either the sporting or comfortable (=automatic) suspension setting.

In the Sports (S) position, the damper curve at the lower end is limited manually. The 5 and 7 Series offer the particularly ambitious and sporty driver the additional possibility of choosing the maximum sports curve at the touch of a button (in which case the button LED (light-emitting diode) lights up on the 7 Series). This programme is then retained until the driver presses the button again for Automatic (7 Series comfort programme, button LED off).

Components :

The system consists of four electronically controlled dampers, each with three response curves (soft, medium and hard).

The parameters considered when adjusting the dampers are road speed, load, transverse acceleration, acceleration in the direction of travel, and vertical acceleration of the vehicle - the following sensors being applied for this purpose :

steering angle sensor
speed sensor on the final drive
vertical acceleration sensor on the front and rear axles

The signal processor, control logics, hardware monitor, and power terminals for feeding an electric signal to the four dampers are integrated in the control unit.