Antilock Brakes / Traction Control Systems: Testing and Inspection

The electrical control unit has a self-diagnosis testing facility. For this reason, it is not possible or necessary to check the control unit unless the check is carried out as part of an ABS test required for other reasons and only when this test is carried out with the Bosch K7-ETT 016.00/VAG 1516 test equipment.
After any work on the braking system which did not affect parts directly involved in the ABS, a function test check is required. The pilot lamp in the instrument cluster will go out when the engine is started if the ABS system is intact. Repairs include replacing brake pads, brake hoses, brake discs, brake unit, tandem master cylinder, brake cables and parts of the parking brake lines not connected to the hydraulic unit.
If work is performed on the hydraulic unit, electronic control unit, wheel speed sensors or the lines or if units are replaced, a function test must be performed with the ABS tester.