Overview - Brake Booster/Brake Master Cylinder, Vacuum Brake Booster

• Brake master cylinder/secondary piston circuit to hydraulic unit
• 14 Nm

There are different versions. Bosch or TRW; note the part number. Refer to Parts Information

Only install brake master cylinder and brake fluid reservoir components from the same manufacturer: Bosch or TRW. Refer to => Electronic Parts Information (ETKA)

• Replace completely if faulty

• 25 Nm

• Replace after removing.

  49 Nm

  55 Nm only for Bosch; note the part number

• To install, coat with brake fluid

• The locking pin must go through the brake fluid reservoir tabs.
• The locking pin must go through the brake master cylinder.
• The locking pin must be tightened.

• 8 Nm

There are different versions. Bosch or TRW; note the part number. Refer to Parts Information

Only install brake master cylinder and brake fluid reservoir components from the same manufacturer: Bosch or TRW. Refer to => Electronic Parts Information (ETKA)

• Fill pressure maximum 6 bar.
  • The locking pin must go through the brake fluid reservoir tabs.
  • The locking pin must go through the brake master cylinder.
  • The locking pin must be tightened.
• Cap: 1.5 ± 0.5 Nm
  NOTE:

  The seal -8- in the cap -9- is not available as an individual part.

  Refer to BRAKE FLUID RESERVOIR, REMOVING AND INSTALLING 

• Replace if damaged

• Equipped on some models

• 8 Nm

• Brake Fluid Level Warning Switch -F34- 

• Replace after removing.

There are different versions. Bosch or TRW; note the part number. Refer to Parts Information

Only install brake master cylinder and brake fluid reservoir components from the same manufacturer: Bosch or TRW. Refer to Parts Information

• Function Test:

  -- With the engine switched off, press the brake pedal firmly several times (to reduce the vacuum in the device).

  -- Hold the brake pedal with average foot pressure and start the engine. If the brake booster is working properly, the brake pedal will be felt to give noticeably under foot (booster becomes effective).

• Refer to BRAKE BOOSTER BALL HEAD, ADJUSTING 

• Replace after removing.

• The pushrod is only loosely inserted into the brake master cylinder and can fall into the brake booster when removing

• For the Brake Lamp Switch -F-
• The actuator pin only functions for the brake lamp, not for the brake system
• If the pin is missing or is damaged, the brake lamp will not function
• Must not fall in the brake booster when removing the brake master cylinder.
• It must always be pushed into the hole in the brake master cylinder directly on the Brake Lamp Switch -F-
• Do not bend it
• Cannot be replaced separately

• Refer to BRAKE LAMP SWITCH, REMOVING AND INSTALLING

• The brake lamp switch must be flush with the outer edge of the mount
• 8 Nm

• Brake master cylinder/primary piston circuit to hydraulic unit
• 16 Nm