Audi Workshop Service and Repair Manuals

Removing and installing brake master cylinder with brake servo Special tools and workshop equipment required

t  Release tool -T40024-

Sealing plug repair kit, Part no. 1H0 698 311 A Removing –  Remove storage compartment on driver's side. → Rep. Gr.68

–  Turn brake light switch -1- 45° in anti-clockwise direction and remove.

–  Use release tool -T40024- to separate brake pedal from brake servo. Extracting brake fluid with upgrade kit and extraction unit -V.A.G 1869/4- or brake filling and bleeding equipment -VAS 5234- –  Detach plenum chamber cover.

–  Lay out sufficient number of lint-free cloths in the area of the plenum chamber. –  Open brake fluid reservoir.

–  Draw off brake fluid.

–  Unplug connector from sender for float warning indicator -1-. –  Pull off vacuum hose -2-.

–  Unscrew securing bolt -1- for brake fluid reservoir.   Note t  Protect the plenum chamber against any brake fluid which escapes. t  The underside of the brake fluid reservoir clips into the brake master cylinder. –  To remove reservoir, press down locking lug and at the same time pull brake fluid reservoir out of sealing plugs. –  Detach brake fluid reservoir and lay it to one side.

–  Unscrew brake lines -1- and -2- and seal with sealing plugs from repair kit, Part No. 1H0 698 311 A. –  Lay out sufficient number of lint-free cloths in the area of the hydraulic control unit.

–  Unscrew brake lines -1- and -2- and remove together with rubber grommet.

–  Unscrew securing bolts for brake servo -1- (Torx -T45-). –  Remove brake servo with brake master cylinder. On vehicles fitted with cross piece the cross piece must be removed. –  Removing and installing cross piece → Rep. Gr.40.

–  Unscrew securing nuts for brake master cylinder -1-. –  Carefully remove brake master cylinder from brake servo. Installing When installing, note the following points in particular: t  Before installing brake master cylinder, clean any residual brake fluid off plenum chamber. t  When assembling brake master cylinder with brake servo unit, make sure push rod is properly positioned in brake master cylinder. –  Adjust brake light switch. –  Bleed brake system → Chapter.