Antilock Brakes / Traction Control Systems: Service Precautions

Notes for repair work on 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 carried out on the vehicle diagnosis, testing and information system VAS 5051.
^ Disconnect battery ground (GND) strap with ignition switched off.
^ When working with brake fluid, observe safety precautions, Refer to Brake Bleeding, Service Precautions.
^ After working on an open brake system, bleed the brake system with VAS 5234 brake filler and bleeder unit, Refer to Brake Bleeding, Service Precautions.
^ During the final road test, make sure that a controlled brake test is performed at least once (pulsations 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 connections and the adjacent areas before loosening, do not use cleaning agents such as brake cleaner, gasoline, or thinners.
^ Place parts that have been removed on a clean surface cover.
^ Cover or seal open components if repairs cannot be completed immediately. (Use sealing plugs repair kit 1 HO 693 311 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 in areas with compressed air and do not move the vehicle.
^ Make sure that brake fluid does not enter harness connectors.
^ When painting, electronic control module can be exposed to a maximum temperature of 95°C only briefly, and a maximum temperature of 85°C for longer periods of time (approximately 2 hours).