Audi A4

since 1994 release

Manual of the car

Audi A4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ System of an exhaust
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and channels of absorption
+ System of injection
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
- Brakes
   Independent work on the brake system
   So the brake system works
   Check of brakes
   Brake fluid
   Check of level of brake fluid
   Check of the brake system on tightness and existence of damages
   Replacement of brake fluid
   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
   Emergency brake
   Check of idling of the lever of the emergency brake
   Main brake cylinder
   Brake amplifier
   Check of the brake amplifier
   Works on hydraulics of the brake system
   Pumping of the 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 work of the ABS system
   Electronic blocking of differential (EDS)
+ Wheels and tires
+ Electrotechnical equipment
+ System of ignition
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics


Works on hydraulics of the brake system


  1. Brake fluid is poisonous. Therefore touch it with a mouth or open wounds.
  2. Brake fluid corrodes an automobile varnish. Therefore do not put on varnishing of a rag, impregnated with brake fluid, or the tools soiled in it.
  3. When weakening a brake hose or brake tube brake fluid gradually follows from a broad tank. Do not allow it as follows: before weakening of screw connection in the corresponding brake contour weaken the pumping screw. Put on a hose of pumping and lower it in capacity. Completely wring out a pedal of a brake and fix it in this situation with the help of a wooden plate. It will close openings of supply of liquid in the main thing brake the cylinder and brake fluid will not pour out any more.
  4. For unscrewing and tightening of brake tubes you have to buy the shown key for brake tubes
  5. For an extraction in an opposite direction of brake hoses you need a rozhkovy key.
  6. After the works which are carried out in hydraulics of the brake system it is always necessary to pump over it. Often happens sufficient to pump over only that brake contour on which work was carried out.

Dismantle of brake tubes


  1. Unscrew a cap nut of a brake tube. Reliably hold opposite connection, for example, on the end of a brake hose.
  2. If the nut on a tube rusted and does not rotate, then anyway the tube needs to be changed. Thin-walled tubes quickly break off.
  3. For unscrewing of connecting knots of tubes the following council can help in case this piece of a tube anyway has to be replaced:
  4. Saw off a brake tube near screw connection, unscrew a cap nut a key like "nutlet" with a hexagon.
  5. Lay brake tubes in the expansion arms intended for them.

Dismantle of brake hoses


  1. In the beginning unscrew a cap nut of the corresponding brake hose. At the same time you watch that the hose was not overwound.
  2. If the brake hose is attached to a body by a metal arm, then it is fixed by a metal collar in order to avoid shifts. At assembly do not forget about this so-called arm of a hose.
  3. At installation always in the beginning screw a hose in that place where it has an external carving.
  4. Then delay other screw connection.
  5. The brake hose should not be overwound. As control serves the color strip or the rubber roller along a hose.
  6. Pump over the brake system.
  7. Right after repair check whether the hose will rub somewhere at the depreciation movements.
  8. Repeat this check after a long trip.