Procedures

Remove/Install Stepped Tandem Brake Master Cylinder

Shown On Model 203 Up To 31.07.01:

Shown On Model 203 As Of 01.08.01:

Remove/Install

DANGER:
- Risk of poisoning from swallowing brake fluid. Risk of injury from brake fluid coming into contact with skin and eyes.
- Pour brake fluid only into suitable and appropriately marked containers. Wear protective clothing and eye protection when handling brake fluid.

CAUTION:
- See brake fluid notes
- See notes on repairs to brake system
- See notes on externally invisible brake fluid loss

DANGER:
- Risk of explosion from explosive gas. Risk of poisoning and caustic burns from swallowing battery electrolyte. Risk of injury through burns to skin and eyes from battery acid or when handling damaged lead-add batteries
- No fire, sparks, naked flames or smoking. Wear protective gloves, acid-resistant clothing and safety glasses. Pour battery electrolyte only into suitable and appropriately marked containers.

1 Disconnect ground cable of battery

CAUTION:
- Model 209: Do not connect quiescent current retention unit as malfunctions in the control modules may occur.

2 Disconnect plug (20) from brake fluid indicator switch (S11)
3 Suction off brake fluid from brake fluid reservoir (10)
4 Disconnect brake lines (5)

NOTE: Seal off connections with plugs.

5.1 Disconnect plug of pressure sensor 2 ESP (B34/2), unscrew pressure sensor 2 ESP (B34/2)

5.2 Disconnect plug of ESP brake pressure sensor (B34), unscrew ESP brake pressure sensor (B34)
- Model 209

6 Detach clutch master cylinder hose (7)
- Vehicles with manual transmission.

7 Remove pendulum support

NOTE: In the case of crashed vehicles with front end deformations, the pendulum support must be checked for clearance.

8 Unscrew fixing nut (19) at the top and bottom of the brake booster (16)
9 Pull stepped tandem brake master cylinder (1) off threaded studs and turn to the side

CAUTION: Do not tilt stepped tandem brake master cylinder (1), but pull out from the front otherwise the thrust rod no longer makes axial contact and can break free of the retaining lugs at the master control unit.

10 Disconnect plug of pressure sensor 1 ESP (B34/1), unscrew pressure sensor 1 ESP (B34/1)

11 Remove stepped tandem master brake cylinder (1)

CAUTION: Installation: Install new gasket (17) to ensure that the brake booster (16) functions correctly.

12 Unscrew bolt (10a)
13 Pull brake fluid reservoir (10) out of the stepped tandem brake master cylinder (1)

CAUTION: Check reservoir plugs (9) replace if necessary in order to avoid leaks

14 Install in the reverse order
15 Bleed brake system.

Inspect
16 Check brake system for leaks