Antilock Brakes / Traction Control Systems: Service Precautions

Notes for repair work on ABS, ABS/EDL
^ Before working on the anti-locking system, determine the cause of the malfunction On Board Diagnostic (OBD).
Refer to Powertrain Management
^ Before working on the ABS, ABS/EDL system, disconnect the battery Ground strap. Obtain coding, on vehicles with coded radio.
^ Before carrying out welding work with an electric welding unit, disconnect the ABS control module.
^ When working with brake fluid, observe the relevant safety precautions and notes.
^ Work for which the brake system has to be opened, bleed the 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 (pulsations must be felt at the brake pedal).
^ Absolute cleanliness is required when working on the anti-locking brake system, it is not permitted to 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, gas, thinners or similar.
^ Place removed parts on a clean surface cover.
^ After separating the control module/hydraulic unit use the transportation protection for the valve dome.
^ Carefully cover or seal open components if repairs cannot be carried out immediately. (Use sealing plugs repair kit 1 HO 693 311 A).
^ Do not use huffy cloths.
^ Only remove replacement parts from packaging immediately prior to installation.
^ Only use genuine packed parts.
^ When the system is open do not work with compressed air and do not move the vehicle.
^ Make sure no brake fluid enters plug connectors.