Mercedes M-Class W163
since 1997 of release
Repair and car operation
+ Mercedes-Benz Cars of a class M (W163)
+ Governing bodies and receptions of safe operation
+ Current leaving and service
+ Systems of cooling, heating and air conditioner
+ the Power supply system and production of the fulfilled gases
+ Systems of electric equipment of the engine
+ Manual box of gear shifting
+ Avtomaticheckaya transmission
+ Transmission line
- Brake and auxiliary systems
General information and security measures
Check of brake system on leaks
Check of serviceability of functioning of the vacuum amplifier of brakes
Check of the transient valve
Removal and installation of the main brake cylinder
Removal and installation of the vacuum amplifier of brakes and sensor of a course of a diaphragm of BAS
Removal and ETS/ESP hydromodulator installation
Removal and installation of the hydraulic lines laid between GTTs and the ETS/ESP hydromodulator
Assessment of degree of wear and replacement of brake shoes
Replacement of brake hoses
Removal and support installation
Removal and installation of a brake disk
Replacement of boots of the parking brake
Pumping of brake system
Removal and installation of pedal knot and sensor switch of stoplights
Removal and installation of a pedal of raising of the parking brake
Removal and installation of hummock assembly of a drive of the parking brake
Adjustment of a drive of the parking brake
Removal and installation of wheel ABS/ETS/ESP sensors
+ Suspension bracket and steering
+ Onboard electric equipment
General information and security measures
The brake system consists of the main brake cylinder, the vacuum amplifier and disk brake mechanisms of lobbies and back wheels and is divided according to the diagonal scheme into two independent hydraulic contours. At refusal of any of contours (for example as a result of sealing violation) the second continues to function in a normal mode, providing adequate braking of a vehicle. In addition the valve regulator of pressure providing dynamic correction of effort of braking of back wheels according to change of load of a back axis of the car is built in contours of both back brake mechanisms. Pressure of liquid in both contours is created by the main brake cylinder (GTTs) having a tandemny design. Activation of GTTs occurs when squeezing a pedal of a foot brake.
Scheme of the organization of a hydraulic actuator of brake mechanisms
The short description of principles of functioning of auxiliary electronic systems of anti-blocking of brakes (ABS), strengthenings of emergency braking (BAS), distribution of brake efforts (EBV), is provided by antiprobuksovochny (ASR/4-ETS) and protivozanosny (ESP) in Head Governing bodies and receptions of safe operation.
Scheme of an arrangement of components of system of strengthening of emergency braking (BAS)
Scheme of an arrangement of components of auxiliary electronic systems ASR/ETS/ESP
The tank with brake liquid is under the main brake cylinder, it supplies with liquid all hydrosystem of braking.
The amplifier of a brake accumulates a part of the vacuum created in the soaked-up pipeline of the engine. As the diesel engine has no necessary vacuum on absorption, cars with the diesel engine have the special vacuum pump. By means of the corresponding valve if necessary the effort to pedals of a brake increases thanks to vacuum action.
The parking brake with a pedal drive influences through cables brake mechanisms of back wheels. In addition back brake mechanisms are equipped with drum-type knots of the parking brake with pedal тросовым a drive.
Principles of functioning of auxiliary systems ABS/4-ETS/ESP/EBV
The electrohydraulic scheme of functioning of auxiliary systems is presented on an illustration which all references meeting in the text concern.
Scheme of a hydraulic contour of auxiliary electronic systems ABS/4-ETS/ESP/EBV
The structure of the hydromodulator of auxiliary brake systems (A7/3) includes components of systems of the closed contour of dynamic control of ABS systems, 4-ETS/ASR and ESP.
Pressure head and returnable pump (A7/3m1)
Being self-filled pressure head and returnable pumps (p1, p2) are built in assembly of the hydromodulator (A7/3) and are switched by pulse signals in phases of forcing and dumping of pressure of system of active management of ETS and ESP, and also during adjustment of a returnable stream at ABS activation.
Being self-filled pressure head and returnable pumps (p1, p2) are started if necessary for the purpose of noise level minimization.
Each brake contour is equipped with the separate damper (10) reducing level of noise made by the pump.
Electromagnetic valves of deduction (inlet) and dumping (final) pressure (A7/3y6 - A7/3y13)
One 2/2-hodovy valve is used at management of pressure in contours of each of wheels in phases of forcing/deduction and deduction/dumping of the operating ABS, ETS and ESP modes.
Low-pressure head accumulator (11)
The low-pressure head accumulator (11) is filled with brake liquid in a phase of dumping of pressure of ABS, ETS or ESP and provides its transfer to pressure head returnable pump (p1/p2).
Operating multiple-pass electromagnetic valves (A7/3y24 and A7/3y25)
Electromagnetic multiple-pass valves switches (and y25) provide with y24 an otsechka of active pressure head diagonal contours from GTTs during ETS and ESP functioning. Also valves provide pressure dumping when lifting it over 150 atm. Brake liquid passed through valves switches goes back to GTTs.
Electromagnetic valves of preliminary filling (A7/3y26 and A7/3y27)
Valves (y26, y27) open in phases of increase of pressure of ETS/ESP.
Principle of functioning of assembly of the sensor of the withdrawing moment / cross-section overloads of ESP
Sensors of the withdrawing moment and cross-section overloads with a view of economy of a place are incorporated in uniform assembly (B24/2). Micromechanical touch assembly will transform cross-section and vertical projections of angular accelerations to electric signals. Various on weight working elements under the influence of arising during not inertial movement of a vehicle (commission of turns and accelerations) overloads provide various extent of deformation. The special electronic converter converts received signals and on the tire CAN transfers them to the module of management of antiprobuksovochny and protivozanosny systems (N47).
The sensitive element of the sensor of the withdrawing moment is created from a micromechanical ring (and), equipped with eight spring crossing points (b) providing its movement and electromagnetic action. At rotation in assembly arise additional кориолисовы the forces proportional to speed of rotation, fixed in an electromagnetic way and, after transformation in the ACIS module in a form of the analog signals, combinations of devices given out on the control unit.
Design of the capacitor sensor of the withdrawing moment of ESP system
The principle of measurement of cross-section overloads is based on use of a spring and mass element with the capacitor detector. Working tension moves from the module of management of ESP (N47-2).
Arising during commission of turns cross-section overloads provide shift of a spring and mass element from position of balance on the size proportional to value of arising force of reaction. Any change in the provision of an element leads to change of capacity of the detector. Further, the fixed size of a deviation will be transformed to the alarm tension allowing the module of management of ESP (N47-2) to make a quantitative assessment of sizes of fixed cross-section overloads.
The electronic module of management watches that the system, in case of mechanical damages of a contour (for example, cable break), or at excessive power failure, was automatically disconnected. The situation is displayed on the dashboard by activation of a control lamp of ABS. At the same time there is a shutdown of ESP and BAS systems that proves to be true operation of the corresponding indicator (see. Head Governing bodies and receptions of safe operation). The main brake system continues keeps thus the working capacity, - during braking the car behaves as if the ABS system is absent.
Activation during movement of a control lamp of ESP testifies to detection of malfunction of the amplifier of emergency braking (BAS) or protivozanosny system (ESP), - the relevant systems thus also are disconnected with preservation of ability of functioning of the main brake system.
At activation during movement of a red control lamp of brake system, it is necessary immediately to stop and try to establish to find out a cause of infringement falling of level of brake liquid, or not up to the end released lever of the parking brake can appear which in particular.
Operations procedure at operation of a control lamp of ABS during movement
Stop the car, switch off the engine and again start it.
Check level of tension of the storage battery, - if the result of measurement makes less than 10.5 In, make battery additional charge.
Make sure of reliability of fastening of tips of wires on polar plugs of the battery, in case of need tighten fixture.
To Poddomkratta the car also establish it on props, remove wheels and check a condition of electroconducting of wheel sensors.
More detailed diagnostics should be carried out in conditions HUNDRED with use of the special equipment for reading written down in memory of the module of management of codes of malfunctions (DTC).