Disassembling and Assembling

Control module and hydraulic unit, disassembling and assembling
This work procedure only applies if the control module is malfunctioning.

If the hydraulic unit malfunctions, the complete hydraulic unit with control module must be replaced.

Note:
^ The sealing surface the hydraulic unit must be clean and undamaged. It must not be refaced.
^ If the sealing surface is damaged, the hydraulic unit with the control module must be replaced complete.
^ The seal at control module must not be removed, it cannot be replaced.
^ The bolts of control module to hydraulic unit must always be replaced after removal.
^ The threads in the hydraulic unit must not be reworked.
^ The hydraulic unit with the control module must be replaced complete, if one or more threads are damaged.
^ After disconnecting control module/hydraulic unit, use transport protection for valve domes.

Special tools and equipment





^ VAG1783 torque wrench

Disassembly
^ Control module with hydraulic unit, removing, Refer to Control Module and Hydraulic Unit, Removing and Installing





^ Remove bolts -1- to -6- from hydraulic unit.
The return pump must not be separated from the hydraulic unit.
^ Carefully disconnect hydraulic unit with hydraulic pump at interface upward from control module.





When removing the control module, be sure that valve domes -1- of hydraulic unit -b- do not jam with the magnetic coils -2- of control module -a-.
Cover control module magnetic coils with a lint free cloth.
Use transport protection for valve domes after disconnecting from control module and hydraulic unit.
^ Check sealing surface of hydraulic unit for scoring, scratches etc. The sealing surface must be undamaged.
If the sealing surface at hydraulic unit is damaged, the hydraulic unit with the control module must be replaced.





^ Check contact springs -1- of return flow pump for burn spots and oxidation. Do not clean the contact springs.
If the contact springs at hydraulic unit are damaged, the hydraulic unit with the control module must be replaced.

Assembly
Vehicles with ASR- and ESP-control module





^ Check in sequence the new control module:
- The surfaces of heat conductor pole -1- for oxidation to ensure good heat conductibility.
- The protrusion dimension of the heat conductor pole, which must protrude 0.8 to 1.0 mm between the upper edge of the heat conductor poles -1- and seal -2-.
- The suspension of the heat conduction poles. For this, the heat conduction poles must be pressed and released again, during which they must spring.

If a problem is detected during a check, the control module must be replaced.

Continuation for all vehicles
^ Clean sealing surface of the hydraulic unit e.g. with mineral spirits.





When attaching control module -a- and hydraulic unit -b-, be sure that valve domes -1- of the hydraulic unit do not jam with magnetic coils -2- of the control module.

^ Set control module onto hydraulic unit.





^ First, thread in new bolts -1- and -2- altermatingly to end by hand.
Ensure that the control module is centered on the groove of the hydraulic unit.
^ Thread in new bolts -3- and -4- and then new bolts -5- and -6aternating to end by hand.
^ Tighten bolts in the sequence -1- and -2-, then -3- and -4- and then -5- and -6- to the specified tightening torque.
^ Control module with hydraulic unit, installing Control Module and Hydraulic Unit, Removing and Installing

Tightening torque:
Control module to hydraulic unit 3 Nm