Volkswagen Workshop Service and Repair Manuals

Location:

The control unit is bolted to the hydraulic unit and is located on left in the engine compartment.

Removing:

• ‒ Obtain radio code on vehicles with coded radio.
• ‒ Disconnect battery.
• ‒ Remove coolant expansion tank and swing to side.

• ‒ → Pull connector off control unit.
• ‒ Fit bleeder bottle bleeder hose to the front left brake caliper bleeder screw and open bleeder screw.
• ‒ Depress brake pedal at least 60 mm.
• ‒ Fit brake pedal loading device from V.A.G 1238 B.
• ‒ Close front left bleeder screw.
• ‒ Remove heat shield from tandem master brake cylinder.

• ‒ Disconnect brake pipes on brake master cylinder and hydraulic unit and seal brake pipes and threaded holes with plugs from repair kit Part No. 1H0 698 311 A.
• ‒ Remove torx socket head bolts T 25 on hydraulic unit bracket.
• ‒ Remove hydraulic unit.
• ‒ Pull hydraulic pump motor connector off control unit.

• ‒ → Remove bolts from control unit and pull control unit off.

Do not cant control unit when pulling off.

Cover control unit solenoids with a lint-free cloth.

After separating control unit/hydraulic unit use transportation protection for valve dome.
=>Booklet Running gear, Technical Bulletin No. 6

Installing:

Notes:

• ◆ Only remove sealing plugs on hydraulic unit when the relevant brake pipe is going to be fitted.
• ◆ If the sealing plugs are removed too early, brake fluid can escape, it can then no longer be guaranteed that the unit is sufficiently filled or adequately bled.
• ◆ There must be nothing in the area of the control unit that can contaminate the valve block.

• ‒ Bolt control unit to hydraulic unit. Observe tightening torque, max. 4 Nm. (Always use screws supplied).
• ‒ Connect hydraulic pump motor connector.
• ‒ Further installation is carried out in the reverse sequence
• ‒ Bleeding brake system =>Booklet Running gear; Repair group 47
• ‒ Coding control unit =>Page 01-113