Mercedes S-Class W-140

1991-1999 of release

Repair and operation of the car



Mercedes S-Class
+ Mercedes-Benz cars of the class S (W-140)
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling systems, heating
+ Power supply system and release
+ Engine electric equipment
+ Gear shifting box
+ Automatic transmission
+ Coupling
- Brake system
   Specifications
   Arrangement of components of the ASR/ETS traction control system
   Arrangement of components of the amplifier of emergency brake application (BAS)
   Arrangement of components of the ESP system
   Dismantling and assembly of the "Tandem" main brake cylinder (MBC) (model 140.028/032/033/135)
   Removal, installation and check of serviceability of functioning of the servo-driver of the vacuum amplifier of brakes
   Removal and installation of a brake support
   Check of thickness of a brake disk and overlays of brake shoes
   Removal and installation of blocks of the parking brake
   Removal and installation of a forward cable of the drive of the parking brake
   Adjustment of the parking brake
   Wheel ABS sensors - installation details
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment






Removal, installation and check of serviceability of functioning of the servo-driver of the vacuum amplifier of brakes

Removal

Details of installation of the servo-driver of the vacuum amplifier of brakes


 PERFORMANCE ORDER

1. Remove the main brake cylinder (see the Section Dismantling and assembly of the "Tandem" main brake cylinder (MBC) (model 140.028/032/033/135)).
2. Remove the supporting pump ASR.
3. Check GTTs for absence of damage and leaks.
4. Turn off or unhook a vacuum tube (8) from the vacuum amplifier (16). Press several times a brake pedal to reduce pressure in the vacuum amplifier.
5. Disconnect the socket (A7/7x1), (A7/7x2) from the BAS control unit or on models with ESP disconnect the socket from the switch of the electromagnetic valve and the sensor of movement of a diaphragm of BAS on the vacuum amplifier. On models about BAS and ESP, the BAS control unit it is integrated with the ESP control unit.
6. Remove the lower cover of the dashboard.
7. Disconnect a returnable spring of a brake pedal.
8. Take a clamp and a finger (26).
9. Turn off a nut (23) from an arm (22).
10. Remove the vacuum amplifier (16).
11. Check laying (16).

Installation

Installation is carried out as it should be, the return to removal.

Check

 PERFORMANCE ORDER

1. Press a brake pedal to reduce pressure in the vacuum amplifier.
2. Disconnect a tester from the vacuum amplifier.
3. Attach the manometer (051) to a brake support with an adapter.
4. Attach the sensor of measurement of effort to pedals (06) on a brake pedal.
5. Start the engine and create pressure of 0.75 - 0.80 bars, pressing and releasing an accelerator pedal. If reach vacuum on value much below, than it is required, or vacuum immediately decreases, then the sealing ring between the vacuum amplifier and the main brake cylinder is damaged or it is necessary to check the valve in a vacuum tube.
6. Create the required effort to pedals of an accelerator and read pressure in the line. Dependence of pressure in a hydraulic actuator from effort of pressing a pedal of a foot brake is given in Specifications.