Part 1 - Introduction

Dynamic Stability Control

Note! Structure of this document.
The most important diagnosis instructions are described at the start of this document. These are followed by the functional description.

Diagnosis Instructions

Remedying faults and/or clearing fault memory
If problems occur on clearing the fault memory following a repair, use the following procedure:
1. Remedy fault with ignition off
2. Switch ignition ON, clear fault memory
3. Switch ignition OFF, wait 5 - 10 seconds, switch ignition on again
4. Clear fault memory again

Important! In some cases, indicator and warning lamps for certain faults only go out after a short test drive.

Sequence for replacement of DSC module or DSC control module
After replacing the DSC unit or DSC control module The parameters for the Run Flat Indicator (RPA) as well as the cruise-control system must be coded using Progman.

With regard to the DSC function, the DSC control module codes itself. In this operation, the vehicle identification number is also saved. This means that calibration of the steering-angle sensor with DSC 8/DSC 8Plus is not required. For every startup (ignition on), the DSC compares the saved vehicle identification number with the current vehicle identification number. DSC codes itself according to the type of vehicle if the vehicle identification numbers do not match. This opportunity is used to reset the learned calibration values of the sensors to the base setting (exception: longitudinal acceleration sensor).

Perform the following operations:
1. Coding DSC
2. Venting routine for DSC unit
3. Check for swapped brake lines
4. Initialize Run Flat Indicator (see owner's manual)

Replacement of DSC sensor
After replacement of the DSC sensor, the service function "Calibration DSC sensor" must be run. The longitudinal acceleration sensor is calibrated in the DSC sensor.

Replacement of steering-angle sensor
The steering-angle sensor forms a unit with the steering column switching center. The steering-angle sensor cannot be replaced on its own. The service function "Calibration steering-angle sensor", or in the case of vehicles with active steering, the service function "Commissioning/Calibration active steering", must be run after the following work:
- Replacement of the steering column switch cluster (SZL)
- Only E60/E61: re-programming of steering column switch cluster (SZL in the E70 not programmable)
- Only E70: replacement of DSC control module (as the SZL is calibrated via the DSC)
- Calibration work on the steering geometry
- Work on the steering and/or front axle

Introduction

Dynamic Stability Control
As series standard, the E70 is equipped with dynamic stability control (DSC).
E60/E61 as of 03/2007.
The DSC is an enhancement of DSC 8Plus. To make a distinction, this chassis control system is called "DSC Premium". System supplier for the DSC is Bosch.

The control functions of the DSC have been optimized. The improvement was achieved by installing a return-flow pump with 6 pistons as well as more powerful electronics. In comparison with the previous model (E53), the E70 has been given extended functions:
- Brake standby through preventive application of the brake pads for when they might be required (build-up of low brake pressure)
- "Dry braking" of the brake discs on wet roads with wipers switched on
- Detection of fading and increase in the brake pressure in the event of fading
- Drive-off assistant
- Cruise control with braking function (optional extra 544)
- Parking brake (electromechanical and hydraulic parking brake)

Further road safety results from the combination with other systems:
- Yaw moment compensation with active steering (optional extra 217)

DSC is a driving dynamics system that maintains driving stability. DSC optimizes:
- driving stability on driving off, accelerating, cornering as well as braking
- traction

The DSC also detects unstable driving states such as understeer or oversteer. DSC helps to maintain the vehicle on a safe course within the physical boundaries.
To do so, the DSC must be aware of the following dynamic measurement variables:
- The yaw rate as a measure for the rotary motion of the vehicle around the vertical axis
- Lateral acceleration
- Wheel speeds

In addition, the driver's demand is detected from the steering angle and the brake pressure the driver applies to the pedal. Furthermore, wheel-speed sensors deliver information on the speed of the individual wheels. The available measured values are used to determine the actual status in which the vehicle is moving at the moment. The actual condition is compared with target values calculated in the DSC control module. If the current actual values deviate from the target state, DSC becomes active and actively intervenes in the brake system or in the engine management system, as the case may be.

Brief Description Of Components

For Brief Description Of Components, please refer to Part 2 - Brief Description of Components

System Functions

For desription of System Functions, please refer to Part 3 - System Functions.

Notes for Service department
General information

Important! Replacing the DSC control module.

On replacement of the DSC control module, the repair instructions must be observed (special tool necessary).

Diagnosis instructions
The following service functions are available in the BMW diagnosis system:
- Brake bleeding procedure
- Check for swapped brake lines
- Steering angle sensor calibration
- Calibration / commissioning of active steering (must be carried out after calibration of the steering-angle sensor)
- Calibration of DSC sensor

Notes on encoding / programming
After replacement, the DSC control module must be encoded.

Switch-on conditions
After every engine start, the DSC is operational.

No liability can be accepted for printing or other faults. Subject to changes of a technical nature