Hydraulic Control Unit: Service and Repair

23 42 533 - Replacing hydraulic unit GS6S53BZ SMG (transmission removed)





Special tools required:
- 00 1 450 00 1 450 Assembly Stand
- 23 0 170 23 0 170 Support





Important!
Before working on hydraulic system:

- Reduce pressure in hydraulic system by means of Service Function in DIS Tester
- Disconnect hydraulic pump relay Service and Repair in electronics box
Do not reconnect relay for entire duration of repair work





Note:
After completing work:

- Check fluid level in hydraulic system Service and Repair by means of DIS Tester "Service Function"
- Perform "Teach in transmission" service function by means of DIS Tester





Mount transmission (1) with special tool 23 0 170 23 0 170 Support in assembly stand 00 1 450 00 1 450 Assembly Stand.





Remove sealing cap (1) using a screwdriver (2).

Service opening must not be damaged. Burr can cause the sealing cap to leak.

Installation Note:
Replace sealing cap.





Release fitting screw (1).

Tightening torque 23 31 3AZ Interior Shift Components.

Installation Note:
Replace fitting screw.





Remove screws (1) and (2).

Tightening torque 23 41 1/7AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.

Pull out shift actuator (4)

Do not detach hydraulic line (3).

Installation Note:
Clean sealing surfaces.

Apply Loctite 574 sealing compound to sealing faces.





Unlock plug (1) and detach from holder.

Release screws (2).

Tightening torque 23 41 7AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.





Unlock plug (1) and detach from holder.

Release screws (2).

Tightening torque 21 52 5AZ [1][2]Clutch Hydraulic System.





Release screw (1).

Tightening torque 23 41 7AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.

Installation Note:
Make sure retainer (2) for heat shield is correctly positioned.





Release screws (1) and (2).

Tightening torque 23 41 7AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.





Release M8 screws (1) and M6 screws (2).

Tightening torque 23 41 7AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.

Tightening torque 23 41 8AZ [1][2]Automatically Shifted Manual Transmission/Transaxle.

Remove hydraulic unit.