General Information

Bleeding the braking system on vehicles with ABS is carried out as for vehicles with conventional braking systems.

Brake fluid must never come into contact with fluids containing mineral oils (oil, gas, cleaning solutions). Oils containing minerals damage seals and boots on brake systems.

Brake fluid is poisonous. Due to its caustic nature, it must also never come in contact with paint.

Brake fluid is hygroscopic, meaning that it absorbs moisture from the surrounding air, and must therefore be stored in air-tight containers.

Rinse off any leaking brake fluid using plenty of water.

Do not reuse brake fluid once drained.

Follow all disposal regulations.

Keep brake fluid containers tightly and securely sealed. This is to make sure that no oil, dirt or cleaning materials and no humidity can enter the container.

Store containers of brake fluid carefully.

Store oil (also hydraulic fluid) and cleaning fluids separately.

Accidentally mixing fluids or even filling the brake system with the wrong fluid must be prevented.

If one chamber of the brake fluid reservoir is completely empty, the brake system must be pre-bled. Refer to HYDRAULIC SYSTEM, PRE-BLEEDING .

Changing brake fluid. Refer to BRAKE AND CLUTCH SYSTEM, CHANGING BRAKE FLUID .

The bleeding of brake system using the : VAS5234  is described.

An initial pressure of 2 bar (29 psi) is required to bleed the ABS Hydraulic Unit -N55-.

To prevent the brake fluid from overflowing from the reservoir, the level must not be over the MAX mark -1-.

Fig 1: Identifying Brake Fluid Level Marks On Reservoir

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.