Control Processing

Control Processing

The DSC controller monitors the following:

- Rotational speeds of the front wheels.
- Vehicle speed.
- Turning angle of the steering wheel.
- Engine speed. (from the DME over the CAN line)
- Accelerator pedal position (from the EML over the CAN line)

The DSC controller processes the input values from the two front wheel speed sensors and the steering angle sensor.

The rotational speeds of the front wheels for the given turning angle are compared with the programmed values stored in the processor.

If a difference occurs between the current driving conditions and the programmed limits set for lateral stability, the DSC will go into a control phase.

The control phase will always start with throttle regulation. The control phase will either open or close the throttle valve depending on the type of lateral instability (understeer/oversteer). The "CAN" line is used to signal the EML control module to position the throttle valves to correct the instability.

If the unstable condition requires it, the DSC can signal the DME control modules to retard the timing to reduce engine power. This signalling also takes place over the "CAN" line.

A severe difference in speeds, or a very unstable situation, would cause the DSC to activate the brake regulation. The brakes on the rear axle would be pulsed to reduce the power being transmitted to the wheels. This control takes place directly through the ABS/ASC+T hydraulic unit.

The control phases are brief and only occur long enough to correct the unstable condition.

The driver is warned of the unstable condition through the ASC/DSC warning indicator flashing in the cluster.