Procedures

Notes for repair work on Anti-lock Braking System (ABS)

Note: Before carrying out repair work on the anti-lock braking system, determine the cause of the malfunction using "Guided Fault Finding".

"Guided Fault Finding" is performed with the Vehicle diagnosis, testing and information system VAS 5051.

Note:
^ Disconnect the battery Ground (GND) cable with the ignition switched off.
^ Before carrying out welding repairs with an electric welding unit, disconnect the ABS control module.
^ When working with brake fluid, observe the relevant safety precautions and notes, Braking system, bleeding.
^ After working on an open brake system, bleed the brake system with brake filler and bleeder unit VAS 5234, Bleeding brake system with brake filler and bleeder unit VAS 5234.
^ During the final road test, make sure that a controlled brake test is performed at least once (pulsation must be felt at the brake pedal).
^ Absolute cleanliness is required when working on the anti-locking brake system. Do not use any products which contain mineral oil, such as oils, greases etc.
^ Thoroughly clean all unions and the adjacent areas before loosening, do not use aggressive cleaning agents such as brake cleaner, gasoline, thinners or similar.
^ Place removed parts on a clean surface and cover.
^ Carefully cover or seal open components if repairs cannot be carried out immediately. (Sealing plugs, use repair kit 1 H0 698 311 A)
^ Do not use fluffy cloths.
^ Remove replacement parts from packaging immediately prior to installation.
^ Use genuine parts.
^ When the system is open do not work with compressed air and do not move the vehicle.
^ Make sure that no brake fluid enters plug connectors.
^ During painting operations, the electronic control module can be exposed to a max. temperature of 95° C for only a short period, and to a maximum of 85° C for longer periods (approx. 2 hours).