51 21 090 Remove and install/replace the door lock of front door on the left or right

Special tools required: 

• 51 2 190

Necessary preliminary tasks: 

• Remove SOUND INSULATION ON FRONT DOOR 

Disengage Bowden cable (2) from outer door handle at marked position.

Installation note: 

Driver's side only: 

Make sure locking pin (1) is correctly seated in mounting of door lock (3).

Lever out locking rod (1) and set aside.

Unfasten plug connection (2) and disconnect.

Release screws (3).

Installation note: 

• Insert door lock (1) and turn in screws (2) but do not tighten
• Slide special tool 51 2 190 into opened rotary striker until striker engages in first stage
  Fig 3: Installing Special Tool (51 2 190) Into Rotary Striker

  Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

• Pre-tension 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 tighten knurled screw (2) by a further 1 to 1.5 turns (max.) (risk of damage).
  Door lock seal must rest uniformly on inner door panel (water ingress).
  Fig 4: Identifying Door Lock, Knurled Screw And Special Tool (51 2 190)

  Courtesy of BMW OF NORTH AMERICA, INC.
• Tighten down door lock screws, tightening torque 51 21 1AZ .

Feed out door lock (2) out past guide rail of power window regulator (1) via door aperture.