Audi A3

since 1997 of release

Repair and car operation

Audi A3
+ Maintenance instruction
+ Current leaving and service
+ Engine
+ Systems of cooling, heating
+ the Power supply system and production of the fulfilled gases
+ engine Electric equipment
+ Manual box of gear shifting
+ Automatic transmission and models with a full drive
+ Coupling and power shafts
- Brake system
   Replacement of forward brake shoes
   Removal and installation of disk brake mechanisms of back wheels
   Check of thickness of a brake disk
   Removal and installation of a brake disk/support
   Adjustment of the parking brake
   Brake liquid
   Air removal from brake system
   Removal and installation of a brake hose
   Check of the amplifier of a brake
   Removal, installation and adjustment of the switch of a stoplight
   Removal and installation of the lever and cable of the parking brake
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Elektroskhema


Air removal from brake system


After the repair of brake system connected with its opening, air can get to system. In this case it is necessary to remove air from brake system. If after pressing a brake pedal the effort of braking appears insufficiently strong, it also indicates hit in air system. In this case it is necessary to eliminate a leakage and to remove air from system.

In conditions HUNDRED air from brake system is removed, and the system is filled with liquid, as a rule, by means of special devices.

At use of this device pressure of filling of system should not exceed 1 bar.

Air can be removed from system and without use of the specified devices. In this case air from system is removed kachatelny movements of a brake pedal. The help of the assistant is for this purpose necessary.

If it is necessary to remove air from all system, he leaves separately from each wheel cylinder. It becomes in case air gets into each brake cylinder. If only one support is replaced or under repair, it is enough to remove air from the corresponding cylinder.

If the tank of brake liquid completely appeared without liquid (for example, owing to a leakage in system or as a result of air removal when forgot to add liquid in the empty tank) air gets into the pump ABS. In this case air from system it is necessary to delete from safety reasons in conditions HUNDRED with use of the special device. In the presence of EDS it is in addition necessary to carry out adjustment with tester application. At installation of a new brake hose it is also necessary to remove air from system with use of the special device.

Order of removal of air the following:

Support back right,
Support back left,
Support forward right,
Support the forward left.

Unions for removal of air should be opened carefully not to curtail them. It is recommended in 2 hours prior to an otvorachivaniye to spray unions means for rust dissolution. If unions all – not to open, it is recommended to address on HUNDRED.
In the course of removal of air watch liquid level in the tank. Level should not decrease essentially. Otherwise air can get to system. Surely fill in in system only new brake liquid!

1. Remove a cap from the union of removal of air on a support. Clear the union, put on it a pure hose. Other end of a hose lower in the capacity half filled with liquid.
2. Ask the assistant to press a brake pedal so many time, how many necessary for creation in pressure system that is felt on resistance on a pedal.
3. At achievement of pressure press a pedal to a floor and do not release it.
4. Unscrew the union of removal of air on a support approximately on a turn floor by means of a cap key. Collect the flowed-out liquid in capacity. As a result of opening of brake system pressure of a pedal weakens.
5. As soon as pressure of liquid falls down, it is necessary to close the union.
6. Press several times on loops of a brake so that to restore pressure of liquid. Press a pedal. Do not remove a foot from a pedal. Hold the union opened until then, pressure will not start to fall down. Close the union.
7. Repeat above the described operation until following from system in capacity liquid will not contain air vials.
8. After completion of operation remove a hose from the union and put on a cap.
9. Air from other wheel cylinders is issued similarly, observing the corresponding sequence.
10. After removal of air add brake liquid in a tank to Mах mark.

inspect reliability:

– Whether fastenings of brake hoses are reliably tightened?
– Whether the brake hose in the holder is fixed?
– Whether unions of removal of air are tightened?
– Whether it is enough in the tank of brake liquid?
– At the working engine check tightness of system. For this purpose press a brake pedal effort of 200-300 N (20-30 kg) during 10 pages. The pedal should not depart. Check on tightness all connections.

11. In summary check work of brake system on the road with not heavy traffic of transport. Thus it is necessary to execute at least one strong braking with ABS use (it is felt on a pulsation of a pedal of a brake).

Watch closely thus a traffic behind.
Brake liquid should be utilized in a special way. At all it is not necessary to throw out it together with a household waste. Local authorities inform drivers on places of possible utilization of dangerous materials.