ABS Repair Instructions

ABS Repair Instructions

• 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".

Vehicle diagnostic tester performs "Guided Fault Finding".

• Turn off the ignition and disconnect the battery Ground (GND) cable.

• Carry out before welding with an electric welding tool.

• When working with brake fluid, observe relevant safety precautions and notes. Refer to => [ Brake Fluid ] Service and Repair.

• After finishing any work that required opening the brake system, bleed the brake system using the brake charger/bleeder unit (VAS 5234). Refer to => [ Hydraulic System, Bleeding ] Hydraulic System, Bleeding.

• During the 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 the control module/hydraulic unit, use the transport protection for valve domes.

• Carefully cover or seal open components, if repairs are not carried out immediately. (Sealing plugs, use repair kit 1 H0 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 the vehicle while the system is open.

• When painting, the electronic control module can be exposed to a maximum temperature of 95 °C (203 °F) only briefly, and to a maximum of 85 °C (185 °F) for longer periods (approximately 2 hours). Make sure that brake fluid does not enter the harness connectors.