Audi 100

1982-1990 of release

Repair and operation of the car




Audi 100
+ 1.1. Governing bodies and devices
+ 2. Technical characteristics
+ 3. Engines
+ 4. Cooling system
+ 5. Exhaust system
+ 6. Power supply system
+ 7. Transmission
+ 8. Running gear
+ 9. Steering
- 10. Brake system
   10.1. Technical characteristics
   10.2. Adjustment of provision of a pedal of a brake
   10.3. Main cylinder of a brake
   10.4. Brake mechanism of a forward wheel of the Teves brand
   10.5. Brake mechanism of a forward wheel of the GIRLING brand
   10.6. Brake disk
   10.7. Case of a bracket and piston
   10.8. Drum brake mechanism of a back wheel
   10.9. Brake drum
   10.10. Wheel brake cylinder
   10.11. Disk brake mechanism of a back wheel
   10.12. Pressure regulator
   + 10.13. Parking brake
   10.14. Anti-blocking system of brakes (ABS)
   10.15. Pumping of brake system
+ 11. Body
+ 12. Electric equipment










10.14. Anti-blocking system of brakes (ABS)

GENERAL INFORMATION

Scheme ABS

1 – sensor of frequency of rotation of a wheel;
2 – brake mechanism of a wheel;
3 – hydraulic block;
3a – the solenoidal valve;
3b – the pump;
4 – main brake cylinder;
5 – control unit;
6 – a control lamp in a combination of devices;
7 – ABS switch

Four sensors of frequency of rotation of wheels, pressure distributor, the electronic control unit, four gear wreaths established on naves of wheels, and also the control lamp and the ABS switch located on the dashboard are a part of ABS. The electronic control unit is installed under a pillow of a back seat. The block obtains data on the frequency of rotation of wheels from sensors and on the basis of these data gives out signals on electromagnetic valves of the distributor of pressure. The distributor of pressure is installed in an engine compartment after the main brake cylinder. On the distributor four electromagnetic valves from which tubes to working cylinders of brake mechanisms of wheels depart are installed. On a control unit signal valves support necessary pressure in a hydraulic actuator of each brake mechanism.


Prevention

When carrying out electrowelding works it is necessary to disconnect a block with wires from the electronic control unit at the switched-off ignition. When coloring a body with the subsequent drying in a chamber at a temperature of 85 °C and above the electronic control unit needs to be removed from the car. Otherwise the control unit can fail.


Removal and installation of the distributor of pressure

Pressure distributor

1 – pressure distributor;
2 – relay of electromagnetic valves;
3 – pump relay;
4 – holder of wires;
5 – cover;
6 – a tube to the brake mechanism
forward right wheel;
7 – a tube to the main cylinder of a brake;
8 – a tube to the brake mechanism of the back
left wheel;
9 – a tube to the brake mechanism of a back right wheel;
10 – nut;
11 – holder;
12 – rubber pillow;
13 – a tube to the brake mechanism of a forward left wheel;
14 – a wire on "weight"

PERFORMANCE ORDER
1. To disconnect a wire from the "minus" plug of the battery.
2. To pump out brake fluid from a tank.
3. To disconnect from the tube pressure distributor.
4. To uncover, having turned out the fastening screw.
5. To disconnect a block with wires from the distributor.
6. To turn off a nut of fastening and to disconnect the wire going on "weight" from the distributor.
7. To turn off nuts of fastening and to remove pressure distributor from an arm.
8. To install pressure distributor upside-down. At installation to replace nuts of fastening and to tighten their moment 7 N · m (0,7 kgfs · м). After installation to pump over system of a hydraulic actuator of brakes.

Removal and installation of the ABS electronic control unit

PERFORMANCE ORDER
1. To disconnect a wire from the "minus" plug of the battery.
2. To remove a pillow of a back seat.
3. To disconnect from the electronic control unit a block with wires, having squeezed a spring clip.
4. To turn off two nuts of fastening and to remove the electronic control unit.
5. To install the electronic control unit upside-down. The block with wires can be connected to the control unit only at the switched-off ignition or the switched-off battery.

Removal and installation of the sensor of frequency of rotation of a wheel

Installation of the sensor of frequency of rotation forward (and) and back wheels

1 – rotary fist;
2 – a block with wires;
3 – holder;
4 – rotation frequency sensor;
5 – laying;
6 – bolt;
7 – nave;
8 – gear wreath;
9 – brake board;
10 – pin;
11 – beam of the back bridge

PERFORMANCE ORDER
1. To remove a wheel.
2. At removal of the sensor of the right forward wheel it is necessary to remove a windscreen washer tank to disconnect a sensor block from a plait of wires, and sensors of back wheels – a back of a back seat. To disconnect a block.
3. To turn off a bolt of fastening and to remove the sensor.
4. To install the sensor of frequency of rotation of a wheel upside-down.