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DSC III







The Steering angle sensor is mounted at the bottom of the steering spindle (in front of the flex coupling) as on the Dynamic Stability Control (DSC) II system.

The sensor is "new" in the fact that it now is equipped with a processor and is directly linked to the CAN bus to communicate with the DSC III module.

The sensor also contains the Electronic Damper Control (EDC) III steering angle sensor in the same housing but it is not on the CAN bus and signal output to the EDC control module is unchanged.

The sensor still utilizes two potentiometers to determine the steering angle and the rate of steering. These are the raw signals the CAN Bus microprocessor utilizes to create the steering angle signal for broadcast on the CAN bus.

As with DSC II, this sensor still requires calibration after repairs to the steering or suspension system (found in DIS Service Functions). Once the calibration is completed the sensor now also sends an identification number over the CAN bus to the DSC III module. The ID provides confirmation in the DSC module that the steering angle sensor is properly calibrated.

If the ID differs due to component swapping it will not be possible to enter the DSC system for diagnosis. The DIS will request that the steering angle sensor be recalibrated using the service functions. Once complete a new ID number is generated and the DSC III control module and Steering angle sensor are properly mated.

The DSC III logic checks the plausibility of the steering angle sensor against the other DSC III inputs (front wheel speeds, rotation and lateral acceleration sensors). If battery voltage is interrupted, the current steering wheel rotation is recalculated by the DSC module evaluating the front wheel speeds.