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Connecting VAS 5051B/ 5052 and selecting functions > < General notes
General information on the anti-lock brake system
General information on the anti-lock brake system
  WARNING
The anti-lock brake system is basically maintenance-free.
Testing, removing, installing and repair work may only be performed by qualified personnel.
Failure to observe the information described in this Workshop Manual may result in damage to the system and could make the vehicle unsafe.
t  Before carrying out repair work on the anti-lock brake system, determine the cause of the problem using self-diagnosis.
t  When installing a new hydraulic control unit, always check its coding. Use vehicle diagnosis and service information system -VAS 5051 B- or -VAS 5052-.
t  Always switch off the ignition before carrying out installation or repair work. On vehicles with a coded radio, find out the anti-theft code and disconnect the battery earth strap.
t  When working with brake fluid, observe the relevant safety precautions and notes → Chapter.
t  Always bleed the brake system (using brake filling and bleeding equipment -VAS 5234-) after all work which involves opening the hydraulic system. In addition, a high- and low-pressure test should be carried out on the brake system → Chapter
t  During the final road test, ensure that at least one ABS-controlled brake application is performed (pulsation should be felt at the brake pedal). See vehicle diagnosis and service information system -VAS 5051 B- or -VAS 5052-.
t  Absolute cleanliness is required when working on the anti-lock brake system; avoid any products that contain mineral oil, such as oil, grease, etc.
t  Thoroughly clean all connections and the adjacent areas before loosening, but do not use aggressive cleaning agents such as brake cleaner, petrol, thinners or similar.
t  Place removed parts on a clean surface and cover them up.
t  Carefully cover or seal open components if repairs are not to be carried out immediately. (Use sealing plugs from repair kit 1 H0 698 311 A.)
t  Do not use fluffy cloths.
t  Only remove replacement parts from packaging immediately prior to installation.
t  Only use genuine spare parts from original packaging.
t  When the system is open do not work with compressed air and do not move the vehicle.
t  Ensure that no brake fluid enters electrical connectors.
   

Connecting VAS 5051B/ 5052 and selecting functions > < General notes