Hydraulic Control Unit, Bosch 5.7

Hydraulic Control Unit, Bosch 5.7

Special tools, testers and auxiliary items required

• Brake pedal depressor (V.A.G 1869/2)

• Sealing plug repair kit (1H0 698 311 A)

The hydraulic control unit is installed on the left hand side of the engine compartment.





Removing

CAUTION!
Brake lines must not be bent.

- Note or request the radio code on vehicles with a coded radio, if necessary.

- Disconnect the negative battery cable.

- Release and disconnect the connector from control unit in the direction of the - arrow -.





- Insert the brake pedal actuator (V.A.G 1869/2 ) between the brake pedal and driver's seat. Depress the brake pedal at least 60 mm.

The brake pedal actuator (V.A.G 1869/2) must remain in position until all the brake lines have been reinstalled onto the hydraulic unit.

• Protect the engine compartment against leaking brake fluid.

- Disconnect the brake lines from the hydraulic unit.

- Loosen the bolt - 1 - and pull the coolant expansion tank out, in the direction of the - arrow -, then swivel the tank to one side. Tightening specification of bolt: 6 Nm





- Seal the brake lines and threaded holes with plugs from the sealing plug repair kit (1H0 698 311 A).





• Protect the plenum chamber and engine compartment against leaking brake fluid.

- Remove the brake lines - 1, 2 and 3 -.

• On vehicles from model year 2002 a flexible hose has been installed as part of the brake lines; on vehicles built before model year 2002 the brake lines have to be disconnected at the brake booster.

- Disconnect the brake lines - 1 - and - 2 - and seal with sealing plugs from the sealing plug repair kit ( 1H0 698 311 A).





- Loosen the connector - 1 -.





- Unclip the brake lines from the bracket - 2 -.

- Release the retaining clip from below - 1 - and pull it out in direction of - arrow -.





- Remove the hydraulic control unit.

Installing

Observe the following:

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

• If the sealing plugs are removed too early, brake fluid can escape, and can no longer be guaranteed that unit is sufficiently filled or adequately bled.

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

- Enter the radio code.

- Connect the negative battery cable.

Tightening Specifications