BMW 7 Series: Driving Dynamics Control

History

Control elements are already installed in a number of BMW vehicles that the driver can use to switch individual systems to a sporting mode. This includes the sports setting of the automatic selector lever. In this case, only the shift characteristics of the automatic gearbox are influenced.

The system behaves in a similar manner when the SPORT button for the Electronic Damping Control or Vertical Dynamics Control (shown below) is used. This only changes the characteristic (hardness) of the shock absorber.

Fig. 28: Identifying SPORT Button, E70/ E71

INDEX REFERENCE CHART

1. SPORT button
2. Vertical Dynamics Control with electronically adjustable shock absorbers

All other drive and dynamic driving systems therefore be found as it would need to remain in their basic setting.

A suitable harmonize the damping action in both sporting compromise for this basic setting must mode and standard mode.

A SPORT button that influences several systems was introduced for the first time in the E85/E86. The corresponding "driving dynamics control" function effects a changeover between a standard mode and a sporting mode in the steering, automatic gearbox and accelerator pedal. This meant it was now possible to coordinate these three systems far more effectively in both modes with the result that the customer now experiences a car that is uncompromisingly tailored to "Sport" in every sense.

Fig. 29: Identifying SPORT Button, E85/E86

INDEX REFERENCE CHART

1. SPORT button
2. Accelerator pedal
3. Automatic transmission
4. Steering

The new driving dynamics control in the F01/F02 contains two groundbreaking new features when compared to the E85/E86:

1. All drive and dynamic driving systems installed in the vehicle are comprehensively switched over.

2. Four settings are available. The status of the Dynamic Stability Control is also taken into account thus ensuring that two additional settings are possible.

The driving dynamics control is operated via a new driving dynamics switch and the DTC button positioned directly in front of it.

The changeover operations for many drive and driving dynamics functions are therefore bundled in the driving dynamics control of the F01/F02. The vehicle as a whole then behaves as the driver would expect in accordance with his/her chosen setting.

This bundling can make the handling characteristics of the vehicle considerably more distinctive and less compromising.

Conversely, many individual, and also sometimes meaningless, combinations are avoided (example: sports steering combined with comfort-oriented damping).

Fig. 30: Identifying DTC Button And Driving Dynamics Switch

INDEX REFERENCE CHART

1. DTC button
2. Driving dynamics switch

Mode of Action of Driving Dynamics Control in F01/F02

Networking of Systems

The systems involved in the "driving dynamics control" function are shown in the following Input/Output illustration.

Fig. 31: Input/Output Signal Diagram - Driving Dynamics Control

INDEX REFERENCE CHART

1. Controller
2. Driving dynamics switch and DTC button
3. Integrated Chassis Management
4. Accelerator pedal
5. Automatic transmission
6. Steering
7. Vertical Dynamics Control with electronically adjustable shock absorbers
8. Active anti-roll bar
9. Dynamic Stability Control
10. Instrument cluster
11. Central information display

The driver operates the driving dynamics control using the driving dynamics switch and the DTC button. The ICM control unit imports the control signals then determines on the basis of this which new mode the driving dynamics control should adopt. The mode thus determined is transmitted to the relevant drive and dynamic driving systems for implementation. These are:

• The engine control system for the accelerator pedal characteristic.
• The electronic gearbox control for driving programs and shift speed.
• The Vertical Dynamics Management system for the Vertical Dynamics Control and Active Roll Stabilization.
• The Dynamic Stability Control.
• The ICM control unit itself that controls the power steering assistance (Servotronic) and the steering-transmission ratio (Active Steering).

The ICM control unit also prompts the display of the relevant mode in the instrument cluster and also in the Central Information Display. In addition to selecting a mode, the driver can use the controller to make further settings.

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