Audi A4

since 1994 of release

Repair and car operation

A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ exhaust System
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and absorption channels
+ injection System
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
- Brakes
   Independent work on brake system
   So the brake system works
   Check of brakes
   Brake liquid
   Check of level of brake liquid
   Check of brake system on tightness and existence of damages
   Replacement of brake liquid
   Disk brakes
   Measurement of thickness of overlays of forward disk brakes
   Check of a condition of brake disks
   Replacement of overlays of disk brakes
   Back disk brakes
   Measurement of overlays of back disk brakes
   Hand brake
   Check of idling of the lever of the hand brake
   Main brake cylinder
   Brake amplifier
   Check of the brake amplifier
   Works on hydraulics of brake system
   Pumping of brake system
   The help at malfunctions
   ABS and EDS
   What does ABS?
   Function of separate knots
   Electronic system of distribution of brake effort (EBV)
   Violations in ABS system work
   Electronic blocking of differential (EDS)
+ Wheels and tires
+ Electrotechnical equipment
+ ignition System
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ body Details
+ Salon
Search of malfunctions
Technical characteristics

Electronic blocking of differential (EDS)

Electronic blocking of differential (Elektronische Differential-Sperre) does not work in the main transfer by means of a mechanical peremykaniye of differential or by means of friction surfaces as it complicates a steering and movement on turns. The letter "e" in EDS abbreviation already speaks about electronics use – in a combination to anti-blocking system:


    When in a start of motion the forward wheel rotates, about it learn sensors of number of turnovers of various value of frequency of rotation of wheels. The combined ABS and EDS control unit puts in action a disk brake on a being turned wheel. It is carried out at the expense of additional pair of electromagnetic valves in the hydraulic ABS module. ABS opens connection from a pressure collector to the wheel cylinder of the corresponding disk brake until the wheel will not be braked so that other forward wheel can transfer effort. As soon as on both wheels there are identical conditions of pro-slipping, the control unit finishes process of adjustment and closes electromagnetic valves. The driver does not need to interfere, he notices differential blocking only on change of nature of noise. To exclude failure, EDS is supervised by the blocking scheme. On the basis of pressure of brakes, and also after the established maximum period of time of EDS it is disconnected to avoid an overload of brakes. For the speed over 40 km/h of EDS are disconnected always. Schemes of electromagnetic valves are so calculated that forward brakes cannot work without control. If the control unit distinguishes failure in EDS work, EDS is disconnected. The system of anti-blocking continues to function. In all cases of Audi it is ready to braking at any time. The device of storing of malfunctions works the same as is described in the section on ABS.