System Faults and Reactions

System Faults and Reactions




CAN Interface

The steering angle value is prepared and is transmitted by the SZL over the CAN Bus. Both of the front wheel speed signals (including the direct DSC wheel speed signal), the vehicle speed reference value and the mileage reading are provided by the DSC control module over the CAN Bus to the EDC-K control module.

Power Supply

Low current supply to the damper valves results in hard damping and a high current results in soft damping. The EDC-K control module determines the setpoints and outputs pulse width modulated (PWM) signals to the damper valves to regulate the current flow. Current flow limitation is ensured by an overcurrent detection and deactivation. All of the analog inputs are protected by diodes against positive and negative overvoltage. The following analog signals are processed by the EDC-K control module:

- Vehicle supply voltage
- EDC-K switched output voltage
- Damper valve voltage and current

Valve Activation/Output Stage Circuit




The solenoid valves have low resistance, approximately 2.2 ohms per valve at room temperature because high current is needed at a low voltage. The current is set in the 0 to 2 Amps range depending on the desired damping force. The setpoint value will not exceed 2 Amps to avoid valve damage. The solenoid valves are connected in series for each axle and are supplied with a ground (PWM for continuous adjustment) from the EDC-K control module.

Controller and Control Display Operation




Sports program: The driver can activate/deactivate the sports program by the Controller in the Control Display menu.

A firmer damping is set when the EDC-K request is set to "SPORT". EDC-K always reverts back to the comfort program each time the engine is restarted.