Mercedes Benz R230 User Manual

1Sensotronic Brake Control(SBC)327 HO 09 SBC (WJB) 03-05-04R230 and W211: Starting MY2003

10Driving with SBC – Delayed Off FunctionTime that SBC remains operational after use:• with vehicle stationary and was locked = 20 seconds• with vehic

11Warning DisplayComplete ESP control module failure -Instrument cluster will scroll through failure displays

12Warning DisplaySBC control module failureCertain faults will trigger audible signal

13SBC Components• Brake Operating Unit (BOU)• Wheel speed sensors• Traction System Hydraulic Unit (A7/3)

14W211 System OverviewSBC control module (A7/3n1)Circuit 30Circuit 87Circuit 31Wheel speed sensorsL6/1, L6/2, L6/3, L6/4Stop lamp switch (S9/1)SBC ped

15R230 System OverviewSBC control module (A7/3n1)Circuit 30Circuit 87Circuit 31Wheel speed sensorsL6/1, L6/2, L6/3, L6/4Stop lamp switch (S9/1)SBC ped

16X11/4 Diagnosis ConnectionX11/4Pin 9Z6/33R230W211A7/3n1SBCN47/5ESPN15/5ESMN51/2ABCX11/4Pin 9A7/3n1SBCN47/5ESPZ70/4N10/1L.F.SAM

17Brake Operating Unit - (BOU)

18Brake Operating UnitThe Brake Operating Unit (BOU) consists of the following:• Brake fluid reservoir(Do not overfill!)• SBC pedal value sensor• Tand

19Master Cylinder• Fluid return line• Supply hose to SBC• Do not overfill• Fluid level sensor• Hydraulic lines to SBC

2ObjectivesAt the end of this presentation, you should be able to:1. Explain the function of and purpose for SBC2. Describe the customer interface wit

20Fluid Reservoir Cover• Ultraviolet protection(211 only)

21Pedal Value Sensor - (B37/1)• Contains two hall effect sensors• Converts pedal travel value to an electrical signal• Provides input to SBCcontrol mo

22BOU Tandem Master CylinderFluid reservoirFloating pistonPrimary pistonBrake pressure simulatorFill valvesGF42.46-P-4200-03SLA7/3y1y2A7/3 - Traction

23Normal Braking - Light PressureA7/3y1y2GF42.46-P-4200-03SL• Driver applies pressure to the brake pedal• Pedal travel sensor sends a signal to A7/3•

24Normal Braking - Increased PressureA7/3y1y2• Increasing pedaltravel causes thelarger spring tocompress, providing harder pedal feel

25Normal Braking - Strongest FeedbackA7/3y1y2• Further pedal travel causes piston to compress rubber bumper, providing greatly increased pedal pressur

26Emergency OperationA7/3y1y2Left frontRight frontGF42.46-P-4200-03SLGF42.46-P-3000SL•All electrical functions canceled• Hydraulic pressure creat

27Traction System Hydraulic Unit (A7/3)Consists of:• SBC control module (A7/3n1)• High pressure charge pump(A7/3m1)• Pressure reservoir

28Traction System Hydraulic UnitA7/3GF42.50-P-4000-03S

29Legend1 Brake Operating Unit2 Brake pressure simulator3 Pressure reservoir7 Left front media separator (dividing piston)8 Right front media separato

3ContentsAdvantages of SBC 5Driving with SBC 8SBC components 13Brake operating unit (BOU) 17Traction system hydraulic unit 27Three pressure stages 32T

30Emergency Operation CircuitGF42.46-P3000SL• Pressure applied directlyto front calipers• y1 and y2 not energized• b1, b3, and b4 pressure sensors may

31Brake Pressure SupplyGF 42.50-P-4000-04S GF42.46-P-0001SL• pressure reservoir charged to 160 bar• the high pressure charge pump runs as needed• pres

32Three Pressure StagesSame pressure stages as used with ABS functions:• Pressure apply• Pressure hold• Pressure release

33Pressure Apply - Rear WheelsGF42.50-P-4000-04SGF42.46-P-1000SLGF42.46-P-4500-02SLReservoir pressureBrake pedal pressure• Brake pedal depressed• B37/

34Pressure Apply - Front WheelsGF42.50-P-4000-04SGF42.46-P-1000SLReservoir pressureBrake pedal pressure• y6 and y8 energized• pressure applied to left

35Pressure Apply - All WheelsGF42.50-P-4000-04S GF42.46-P-1000SL• Outlet control valves y7, y9, y11, y13 energized

36Pressure Hold - All WheelsGF42.50-P-4000-04S GF42.46-P-1000SL• y6, y8, y10, y12 de-energized

37Pressure Reduction - All WheelsGF42.50-P-4000-04S GF42.46-P-1000SL• y7, y9, y11, y13 de-energized

38Temperature CompensationDuring continuous brake use the fluid in the calipers expand, this:• creates high pressure • prevents valves 7 & 8 from

39DeactivationDeactivating the system will:• empty the pressure reservoir(a lower pressure with no volume may be retained)• prevent the charge pump fr

4SBC Incorporates these Functions:ABS (Anti lock Brakes 1984)+ ASR (Automatic Slip Regulation 1991)+ ETS (Electronic Traction System 1995)+ ESP

40DeactivationSBC must be deactivated PRIOR to:• working on the hydraulic system• removing or installing brake pads• replacing rotors• replacing the p

41DeactivationCharge pump disabled and accumulator fluid returned to the reservoir! Pressure at A7/3b2

42System ActivationActivation must be performed anytime the system has been deactivated, BEFORE the engine is started!Failure to activate will prevent

43System Activation

44Activation - Left FrontCaliper held with ~60 bar

45Activation - Right FrontCaliper held with ~60 bar

46Activation - Right RearCaliper held with ~60 bar

47Activation - Left RearCaliper held with ~60 bar

48Activation - Recharge

49Bleeding the Brake SystemProper system bleeding is critical!Follow directions in SDS• Bleeding must be performed using the SDS• Pressure at bleeder

5Advantages of SBC• Improves metering of required brake pressure– each wheel can be precisely controlled• Improved BAS function– monitors release of a

50Equipment Required• Pressure bleeder• Adapters• Fluid receptacle • SDS - follow instructions carefullyCAUTION:Extremely high pressure at bleeder! 21

51Bleeding the Brake SystemAR42.10-P-0012RConnect equipment and follow steps in SDS

52Acronym List(Used in This Handout.)ABS - Anti-lock Brake SystemASR - Anti Slip RegulationBAS - Brake Assist SystemBOU - Brake Operating UnitCAN - Co

53AppendixAR42.10-P-0010I Carrying out bleeding operation AR42.10-P-0012R Bleeding system with Star Diagnosis GF42.45-P-0001-04SL ESP driver inform

6Advantages of SBC• Electronic Brake Proportioning: EBP– allows brake proportioning front to back and side to side• No pedal vibration during ABS oper

7Advantages of SBC• Pressure reduction at standstill– reduces stress on components• Dry braking function – wiper input via CAN– ~every 7 to 14 minutes

8Driving with SBC - Wake-UpSBC is functional as soon as it is “wakened” by:• opening a door (via CAN)• operating the central locking system (via CAN)•

9Driving with SBC – Pre-Drive Check (PDC)When SBC performs a PDC after a "wake-up", the following are checked:Warning! Pressure is applied t