ACTi E46 User Manual Page 1

Table of ContentsE46 TRACTION AND STABILITY CONTROLSYSTEMSSubject PageMK20 EI ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10E46 Traction and Stability Control Systems

11E46 Traction and Stability control systemsCOMPONENTSCONTROL MODULE/HYDRAULIC UNITThe control module is installed in the engine compartment, on the r

12E46 Traction and Stability Control SystemsWHEEL SPEED SENSORSThe E46 DSC III system uses the same inductive wheel speed sensors from the ASC system.

13E46 Traction and Stability control systemsBRAKE FLUID LEVEL SWITCHFluid level switch is incorporated into the brake master cylinder reservoir. If th

14E46 Traction and Stability Control SystemsSTEERING ANGLE SENSORThe steering angle sensor is mounted at the bottom of the steering column, in front o

15E46 Traction and Stability control systemsCAN INTERFACEThe DSC control module communicates over the CAN line for the following:• Steering angle from

16E46 Traction and Stability Control SystemsROTATION RATE SENSORThe rotational rate sensor is mounted under the driver's seat. It provides a sign

17E46 Traction and Stability control systemsLATERAL ACCELERATION SENSORThe lateral acceleration sensor is mounted in the left "A" pillar. Th

18E46 Traction and Stability Control Systems

19E46 Traction and Stability control systemsHYDRAULIC SYSTEM COMPONENTSPRE-CHARGE PUMPThe pre-charge pump is installed between the master cylinder and

Subject PageExpansion Tank and Brake Fluid Level Switch. . . . . . . . . . .30Brake Pressure Sensors. . . . . . . . . . . . . . . . . . . . . . . . .

20E46 Traction and Stability Control SystemsMASTER CYLINDER/FLUID RESERVOIRThe master cylinder contains the central valves in both the front and rear

21E46 Traction and Stability control systemsDSC HYDRAULIC OPERATION Based on the programming of the DSC control module, hydraulic intervention can be

22E46 Traction and Stability Control SystemsDIAGNOSISTroubleshooting the E46 TEVES DSC system is carried out using the DIS or MoDiC.The fault indicato

23E46 Traction and Stability Control SystemsTEVES DSC III MK60Model: E46 (except M3 and Xi) and E36/7 Production Date: From 9/00ObjectivesAfter comple

24E46 Traction and Stability Control SystemsPurpose of the systemDSC III MK60 is supplied by Continental Teves and supersedes the Teves DSC III MK20 E

25E46 Traction and Stability Control SystemsKL 30KL 30KL 15KL 15KL 15KL 15DSC SWITCHDSC SWITCHWHEELWHEELSPEEDSPEEDSENSORSSENSORSDIAGNOSISDIAGNOSISABS

26E46 Traction and Stability Control SystemsSystem ComponentsThe Teves DSC III MK60 consists of the following components:• Integrated Control unit/Hyd

27E46 Traction and Stability Control SystemsControl Unit/Hydraulic UnitThe MK60 control unit/hydraulic unit is locatedin the engine compartment on the

28E46 Traction and Stability Control SystemsMK60 Hydraulic UnitThe hydraulic unit consists of an aluminum block containing 12 solenoid valves, 2 press

29E46 Traction and Stability Control SystemsCAN InterfaceThe MK60 is connected to the CAN bus for communication with the AGS, DME controlmodule, Steer

MK20 EI ASCModel: E46/4Production Dates: 6/98 to 6/99ObjectivesAfter completing this module you should be able to:• Identify the communication link be

30E46 Traction and Stability Control SystemsTandem Master Brake CylinderThe MK60 system uses a tandem master brakecylinder fitted with central valves

31E46 Traction and Stability Control SystemsBrake Pressure SensorsTwo brake pressure sensors are mounted on the master cylinder below the outlet ports

32E46 Traction and Stability Control SystemsWheel Speed Sensors (active)With the introduction of the Teves DSC III MK60, active wheel speed sensors th

33E46 Traction and Stability Control SystemsAs the high portion of the pulse wheel approaches the sensing element, a deflection of themagnetic field s

34E46 Traction and Stability Control SystemsDifferent sensors are used on the left and right sidefront axle of the vehicle. The difference comes in t

35E46 Traction and Stability Control SystemsRotation Rate SensorThe Rotation Rate Sensor is mounted on a metal bracket under the drivers seat. The se

36E46 Traction and Stability Control SystemsSteering Angle Sensor (LEW)The Steering Angle Sensor is mounted towards the lower end of the steering colu

37E46 Traction and Stability Control SystemsTransverse (Lateral) Acceleration Sensor The Transverse Acceleration Sensor is mounted in the left “A” pil

38E46 Traction and Stability Control SystemsDSC ButtonThe DSC button is located on the SZM, however the SZM provides no processing, it is simply a hou

39E46 Traction and Stability Control SystemsInstrument Cluster Warning IndicatorsThree warning indicator lamps are arranged in the instrument cluster:

MK20 EI ASCASC was standard equipment on both the 1999 323i and 328i Models. The Teves -Mark 20 EI system is used for the E46. The theory/operation

40E46 Traction and Stability Control SystemsPrinciple of OperationThe scope of control for the MK60 DSC III is comprised of three systems:•ABS• ASC+T•

Pressure Build already occurs during normal braking, so when ABS first intervenes it willstart holding pressure by energizing the Inlet Valve. For exa

42E46 Traction and Stability Control SystemsABS Sub-functionsCorner Brake Control (CBC)CBC can occur if the vehicle is cornering and ABS regulation is

43E46 Traction and Stability Control SystemsElectronic Brake Force Distribution (EBV)EBV will adjust brake pressure to the rear axle based on the rate

44E46 Traction and Stability Control SystemsAutomatic Stability Control (ASC+T)Based on input from the wheel speed sensors, the MK60 control unit dete

45E46 Traction and Stability Control SystemsThe MK60 can control longitudinal wheel slip by two means:• Engine Intervention • Brake Intervention (ADB,

46E46 Traction and Stability Control SystemsSelect-High RegulationIn a Select-High regulation, the MK60 control unit selects the drive wheel with the

47E46 Traction and Stability Control SystemsModified ADB function (2-wheel drive vehicles equipped with MK60)The ADB is an automatic differential lock

48E46 Traction and Stability Control SystemsDynamic Stability Control (DSC)With the introduction of DSC systems, lateral dynamics were taken into acco

49E46 Traction and Stability Control SystemsUndersteerUndersteer occurs when the driver wishes to turn a corner but despite the front wheelsbeing turn

The Mark 20 EI system includes the Cornering Brake Control (CBC) utilized in the BoschASC 5 system. This feature reduces pressure build-up on the insi

50E46 Traction and Stability Control SystemsJust as an ASC regulation, DSC brake intervention carries out:• Pressure Build• Pressure Hold• Pressure re

51E46 Traction and Stability Control SystemsOversteerOversteer occurs when the driver wishes to turn a corner and the tail of the vehicle slidesoutwar

52E46 Traction and Stability Control SystemsBrake intervention is carried out by the MK60 hydraulic unit if the driver is not activelybraking. An exa

53E46 Traction and Stability Control SystemsDSC Sub-functionsDynamic Brake System (DBS)DBS is designed to assist the driver in emergency braking situa

54E46 Traction and Stability Control SystemsMaximum Brake Control (MBC)The MBC function is designed to support driver initiated braking by building up

55E46 Traction and Stability Control SystemsWorkshop HintsDiagnosisDiagnosis of the MK60 DSC III is carried out using the DISplus or MoDiCControl Unit

56E46 Traction and Stability Control SystemsCodingCoding must be performed after replacementof the MK60 control module or the steeringangle sensor. Z

ELECTRONIC BRAKE PROPORTIONING (EBV)A new feature of the Mark 20 EI system is the Electronic distribution of the braking force(EBV). This feature will

DSC III MK20 Model: E46 all versions except all-wheel driveProduction Dates: 6/99 to 9/00ObjectivesAfter completing this module you should be able to

8E46 Traction and Stability Control SystemsINTRODUCTIONThe DSC III system was introduced for the E46, beginning with Model Year 2000 produc-tion (E46/

9E46 Traction and Stability control systemsDSC CONTROL OVERVIEWThe Teves DSC system maintains the lateral location forces during all phases of operati