Electronic Brake Control Module: Service and Repair

Control Module and Hydraulic Unit

Special tools, testers and auxiliary items required

• Torque Wrench 5-50 Nm (V.A.G 1331)

• Torque Wrench (V.A.G 1410)

• Brake Pedal Actuator (V.A.G 1869/2)

• Hose Clamps up to 25 mm Dia. (3094)

Sealing Plug Repair Set, Part No. 1H0 698 311 A





1 Transport protection for valve domes (foam)
2 Sealing Plug M 10
3 Sealing Plug M 12

Removing

Component location:

The control module is bolted to the hydraulic unit and is located at the right in the engine compartment.

Do not bend the brake lines near the hydraulic unit.

- Read and note the present control module coding.

- If the vehicle has a coded radio, get the radio code from the customer before beginning.

- Disconnect the battery.

- Remove engine cover.

6-Cylinder Engine

- Disconnect the knock sensor and vacuum hose valve connectors at rear of intake manifold. Unclip wiring harness from retainers on coolant pipe and lay it aside.

- Remove the vacuum hoses on the rear of the intake manifold, remove from retainers and set aside completely.

- Remove the rear coolant pipe to the side and behind the engine.

- Disconnect the coolant hose on the reservoir with (3094).

- Now remove the coolant hose on the reservoir and then set them as far aside as possible with coolant pipe.

All Vehicles

- On vehicles with heat shield, remove heat shield.

- Press the red securing clip in direction of - arrow - toward the rear.






- Release and remove connector from the control module in direction of - arrow -.






- Insert (V.A.G 1869/2).

- Attach the bleeder hose of bleeder bottles to left front and left rear brake caliper bleeder valves and open bleeder valves.

- Operate brake pedal using (V.A.G 1869/2) at least 60 mm.

- Close left front and left rear bleeder valves.

- Do not remove (V.A.G 1869/2).

- Place sufficient lint-free cloths under the control module and hydraulic unit.

Make sure that brake fluid does not come in contact with the terminals.

- First, mark both brake lines from the master cylinder and remove from the hydraulic unit.

- Plug the brake lines and threaded holes immediately with sealing plugs from the repair kit Part No. 1H0 698 311 A.

- Mark, unfasten and plug the remaining brake lines (brake calipers).

- Lift the hydraulic unit with the control module up and out of the dampers - arrow -.






Installing

• Do not remove sealing plugs at the new hydraulic unit until the corresponding brake line is about to be installed.

• If the sealing plugs are removed too early, brake fluid can escape and the unit may not be sufficiently filled or adequately bled.

• When installing the hydraulic unit, make sure the damper rubber is not pushed out of the bracket.

- Install in reverse order of removal.

Fastening sequence of brake lines:






- Remove (V.A.G 1869/2).

- Bleed the brake system. Refer to => [ Hydraulic System, Bleeding ] Hydraulic System, Bleeding.

- Enter radio code.

- Code the ABS control module (J104) with the vehicle diagnostic tester in "Guided Fault Finding".

A steering angle sensor (G85) , transverse acceleration sensor (G200) , longitudinal acceleration sensor (G251) and brake pressure sensor 1 (G201) basic setting must be done.