Service of Audi A4 from 2001 to 2005 release.
1. Operation and maintenance of the car
2. Engine
3. Transmission
4. Running gear
5. Steering mechanism
6. Brake system
6.1. Preliminary checks
6.2. Repair of the brake system
6.2.1. The amplifier of the brake drive of tandem type / the main brake cylinder in cars with the left wheel
6.2.2. Removal and installation of the vacuum pump of brakes
6.2.3. Removal and installation of the sensor of pressure of the amplifier of the brake drive
6.2.4. Electric vacuum pump
6.3. Repair of brakes of forward wheels
6.4. ABS system
6.5. Tables
7. Onboard electric equipment
8. Body
9. Schemes of electric equipment
 

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6.2.4. Electric vacuum pump

Description and work
The electric vacuum pump is installed only on cars with the automatic transmission. It joins the engine control unit depending on air pressure in an inlet collector.
The vacuum pump has self-diagnostics. The found malfunctions remain in memory of the control unit of the engine.
Check of operation of the electric vacuum pump by method of self-diagnostics is allowed only at the stopped engine.

6.2.3. Removal and installation of the sensor of pressure of the amplifier of the brake drive
6.3. Repair of brakes of forward wheels