EDC-K system function

The EDC-K system is a microprocessor-controlled adjusting shock absorber system. The EDC-K system consists of mechanical, hydraulic and electronic components. Sensors are used to detect handling dynamics, and road surface characteristics. In response to that measured data, the control module makes adjustments to the shock absorbers. In this way, body and wheel oscillation is suppressed as required by the particular circumstances. In addition, the driver can choose between a comfort and a sports program. Immediately after starting the engine, the EDC-K is always in Comfort mode. At a standstill, the shock absorbers are without current; as of approx. 5 km/h, the shock absorbers are supplied with current. In the event of a fault, the system shuts itself down and the shock absorber valves are then de-energized. When that happens, the suspension may feel very hard but the vehicle is nevertheless safe to drive. Valve, sensor, electrical circuit and control-module faults are detectable as system faults. Once a fault has been detected, it remains registered for the rest of the journey. Detection of a sensor fault results in a fixed current being applied to the valve output stages (medium damping force) or the system shutting down completely (very high damping force).

In terms of function, the EDC-K can be divided into three blocks:

• Control module
• Sensors and program selection
• 4 electronically infinitely variable shock absorbers