BMW 7 Series: Service Information

Important Points for Servicing and Repairs

Dynamic Stability Control (DSC)

General details

NOTE: The modes "Dynamic Traction Control" (DTC) and "DSC off" are still used on the F01/F02. However, on the F01/F02, the DSC modes are integrated in the "dynamic handling control" function, which rather than controlling individual systems, controls the system complex of all drivetrain and dynamic handling systems.

NOTE: There is a new set of symbols for DSC displays and controls on the F01/F02.

Fig. 64: Identifying DSC Symbols

Automatic hold function

The Automatic Hold function is activated/deactivated by means of a button on the center console control panel.

The Automatic Hold status is indicated by the function indicator lamp on the button and an indicator lamp on the instrument cluster.

Fig. 65: Instrument Cluster Display - Automatic Hold Indicator Lamp

For Automatic Hold to be activated, the driver's seatbelt must be fastened and the driver's door closed.

NOTE: Before the vehicle is driven into a car wash, the Automatic Hold function has to be deactivated as otherwise the brakes are applied when the vehicle is stationary and it can not be rolled.

DSC unit

There are two versions of the DSC unit which have either one or three pressure sensor(s) (vehicles without/with "Active Cruise Control" optional extra)

NOTE: The repair kits available are either

• the complete DSC unit with pre-filled hydraulic modulator or
• the DSC control unit on its own.

The hydraulic modulator can not be replaced separately.

NOTE: The DSC unit is located in the vehicle underbody, set back somewhat from the wheel arch.

NOTE: If the DSC unit has to be replaced, first of all the vehicle underbody trim has to be removed.

The short lengths of hydraulic pipe subsequently have to be removed and fitted to the new DSC unit.

Signals and sensors

NOTE: The wheel speed sensors are connected to the DSC control unit. The DSC control unit processes the wheel-speed sensor signals and broadcasts them via the FlexRay network to other systems, in particular the Integrated Chassis Management.

NOTE: The DSC control unit does not only provide the wheel-speed signals in the form of bus signals. They are transmitted to the EMF, CAS and TCU control units by direct wired links.

NOTE: The DSC sensor, which was a separate component on previous vehicles, has been integrated in the ICM control unit. The ICM control unit processes the important sensor signals for the Dynamic Stability Control and supplies them in the form of bus signals. Those signals are:

• Yaw rate
• Transverse acceleration
• Linear acceleration
• Steering angle
• Vehicle speed.

NOTE: The DSC sensor in the ICM control unit has to be calibrated if

• the ICM control unit has been replaced or
• the testing sequence on the diagnosis system demands it on the basis of a fault memory entry.

Calibration must be performed with the vehicle on a surface that is level both lengthways and side to side. Terminal 15 must also be switched on.

NOTE: If at least one of the following conditions exists, the steering column switch cluster has to perform steering-angle sensor calibration:

• Wheel alignment carried out
• SZL replaced or re-programmed
• Diagnosis system test procedure specifies calibration.

NOTE: When calibrating the steering angle sensor, the instructions given by the diagnosis system must be followed precisely.

The vehicle must be standing on a level surface during calibration. The steering wheel must be aligned visually in the straight-ahead position.

READ NEXT: