Front Door Latch: Service and Repair

51 21 090 - Removing and installing/replacing door lock in left or right front door





Special tools required:
- 51 2 190
- 51 3 300





Necessary preliminary tasks:
- Remove front door window glass Service and Repair





Release screws (1) on H-strut.
Tightening torque 51 21 13AZ [1][2]Door Locks.
Remove H-strut (2).
Release screw (3) with special tool 51 3 300.
Tightening torque 51 21 14AZ [1][2]Door Locks.
Release screw (4).
Tightening torque 51 21 14AZ [1][2]Door Locks.
Window rail (5) remains in door.





Unlock and disconnect plug connection (2) at lugs (1).
Unhook Bowden cable (3) from door lock (4).
Unclip lock knob control rod (5).





Release screws (1).
Door crashpad (2) remains in door.





Important!
Do not damage door lock seal during removal.

Release screws (1).

Tightening torque 51 21 1AZ [1][2]Door Locks.
Remove door lock (2) from door (3).





Unhook Bowden cable (1) from door lock (2).

Important!
Bowden cable (1) must:
- correctly located in mountings on door lock (2)
- be laid without kinks in bend to door lock (2)





Installation:
Seal (1) on door lock (2) must not be damaged.





Installation:
- Install door lock and insert screws (1), do not tighten down.
- Slide special tool 51 2 190 into opened rotary latch until latch engages in first stage.





Installation:
- Pretension door lock (1) with knurled screw (2) until special tool 51 2 190 just contacts corner points (3).

Important!
To tension door lock (1), it is only permitted to turn knurled screw (2) by a further 1 to 1.5 turns (max.) (risk of damage).
Door lock seal must rest uniformly on inner door plate (water ingress).

- Tighten down door lock screws, tightening torque 51 21 1AZ [1][2]Door Locks.