Note. The main brake cylinders are non-separable, i.e. their repair is not provided. Use only new brake fluid. Follow the instructions on the brake fluid packaging!
Brake booster/master cylinder parts and assemblies 1. Brake fluid reservoir. It is not allowed to remove the mesh filter located in the brake fluid reservoir; 2. Brake fluid reservoir cap. Not installed on all vehicles. The cap is not installed on all vehicles; 3. Plug with cover and brake fluid level signal contact "F34"; 4. Bolt. 5 Nm; 5. Line to the clutch master cylinder; 6. Brake booster. Adjust the ball head. Checking the functionality: with the engine off, press the brake pedal hard several times (this will allow the residual vacuum in the booster to be released). Now, applying medium force, hold the brake pedal in the braking position and start the engine. If the brake booster is in order, then the pedal under your foot will noticeably go down (the boost is in effect). With glued seal. In case of failure, it is replaced entirely; 7. Pedal support bolt. 20 Nm; 8. Brake pedal; 9. Brake light sensor; 10. Bolt. Connects the brake booster to the support bracket. 25 N·m; 11. Hexagonal nut of the main brake cylinder. 49 Nm; 12/13. Brake line. Master brake cylinder to hydraulic unit. 14 Nm; 14. Gasket. Replace; 15. Main cylinder. Cannot be repaired. In case of malfunction, it is replaced entirely; 16. Sealing plug. Moisten with brake fluid and press into the brake fluid reservoir
(The original text is available on the website: audimanual)