Abs Repair Information

• Before carrying out repair work on the anti-lock braking system, as well as the control module coding, determine the cause of the malfunction using "guided fault finding".

"Guided fault finding" is performed with On Board Diagnosis, using the Vehicle Diagnosis, Testing and Information System VAS 5051.

• Disconnect the negative cable (GND) from the battery with the ignition off.
• Carry out before welding with an electric welding tool.
• When working with brake fluid, observe relevant safety precautions and notes. Refer to BRAKE SYSTEM, BLEEDING .
• After finishing any work that required opening the brake system, bleed the brake system using the Brake Charger/Bleeder Unit VAS 5234 or V.A.G 1869. Refer to BRAKE SYSTEM, BLEEDING .
• During final road test, carry out at least one ABS-controlled braking operation (appropriate pulsations must be felt at brake pedal).
• Absolute cleanliness is required when working on the anti-lock 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, fuel, thinners or similar chemicals.
• Place parts that have been removed on a clean surface and cover.
• After disconnecting control module/hydraulic unit, use transport protection for valve domes.
• Carefully cover over opened components or seal, if repairs are not carried out immediately. (Use Plugs 1H0 698 311 A).
• Only use lint-free cloths.
• Only unpack replacement parts immediately prior to installation.
• Only use parts in their original packaging.
• Do not work with compressed air and do not move vehicle while the system is open.
• When painting, electronic control module can be exposed to a maximum temperature of 95 °C only briefly, and to a maximum of 85 °C for longer periods (approximately 2 hours). Make sure that brake fluid does not enter harness connectors.