Removing The Brake Master Cylinder

WARNING: This page is about a different car, the 2010 Porsche Cayenne, 2009 Porsche Cayenne, and 2008 Porsche Cayenne. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Brake Master Cylinder

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Information

Before disconnecting the connector from the brake master cylinder (pressure sensor) first wipe off any moisture with a lint-free cloth.
Brake lines are to be sealed with suitable plugs.
In order to catch escaping brake fluid, place a cloth under the brake booster.

Information

In the case of assembly work on the hydraulic connections, the electrical plug connections on the brake master cylinder must always be connected. This prevents the plug connections on the brake master cylinder and the inside of the plugs being splashed with brake fluid or water.
Clean any plug connections that have become dirty or damp during removal or fitting with a lint-free cloth.
Brake fluid on electrical contacts (even thinned brake fluid) leads to corrosion and may cause faults in the system.
Remove any escaping brake fluid immediately; if necessary, rinse with water and dry.

The brake master cylinder is located on the left in the engine compartment, under the cowl panel cover -arrow- on the brake booster.

Fig 2: Locating Brake Master Cylinder

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Push both connectors -arrows- on the plenum panel (oxygen sensor cable) from the bracket.

Fig 3: Locating Plenum Panel Connectors (Oxygen Sensor Cable)
Courtesy of PORSCHE CARS NORTH AMERICA, INC.
Open the cable clip on the plenum panel and loosen the cable.
Remove left plenum panel partition.
Disconnect the connector on the cover of the brake fluid reservoir and remove the cover -arrow- .

Fig 4: Locating Brake Fluid Reservoir Cover
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Remove the brake fluid from the brake fluid reservoir by suction. To do this, use a double-acting hand pump.
Bend both lugs on the brake fluid reservoir carefully outward and pull off the container upwards. → Fig 5

Fig 5: Identifying Brake Fluid Reservoir Lugs
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Loosen the brake lines from the brake master cylinder.
Unclip the brake line on the brake master cylinder to the left front wheel and remove the fastening clip -arrow- .

Fig 6: Locating Fastening Clip
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Remove the brake master cylinder from the brake booster.
Remove the connector of the pressure sensor at the underside of the brake master cylinder.