51 21 090 Removing and installing/replacing door lock in left or right front door (up to 09/00)

A 4 mm A/F Allen key is required for adjustment.

Detach power window rail at rear (do not remove).

Driver's side only:

Remove complete lock cylinder.

Disconnect plug connection (1) on door lock (2).

Fig 1: Disconnecting Plug Connection On Door Lock

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Release screws (1).

Remove door lock (2) with linkage (3).

Installation: 

Insert linkage for locking knob through opening in inner door plate.

Do not bend linkage (3).

Make sure that the lock lever is inserted between the "outside door handle" support member and outer skin.

Replace screws (1).

Tightening torque, refer to 51 21 1AZ in BODY EQUIPMENT - TIGHTENING TORQUES - 325I, CI & XI - E46 .

Fig 2: Removing Door Lock With Linkage

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Installation: 

Left door lock of front door:

Slacken adjusting screw (1) on door lock (2)

(turn counterclockwise, as shown in illustration),

the lock lever (3) can thus be moved.

Fig 3: Slacking Adjusting Screw On Door Lock

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Coupe/convertible:

For the coupe, the door lock (2) is adapted to the different door geometry.

The illustration shows the left driver's door lock.

Fig 4: Identifying Left Driver'S Door Lock

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The adjusting procedure is identical to that for the saloon/sedan.

1. Adjusting screw (4 mm A/F)

Installation: 

Right door lock of front door:

Slacken adjusting screw (1) on door lock (2) (turn clockwise, as shown in illustration), the lock lever (3) can thus be moved.

Fig 5: Slacking Adjusting Screw On Door Lock

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Coupe/convertible:

Lever out sealing cap (1) for following adjustment.

Fig 6: Levering Out Sealing Cap

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Installation: 

After installing lock cylinder (51 21 140) and/or cover (51 21 180),

Lever out sealing cap (2).

Tighten down adjusting screw (1) on door lock and fit sealing cap (2).

Tightening torque, refer to 51 21 4AZ in BODY EQUIPMENT - TIGHTENING TORQUES - 325I, CI & XI - E46 .

Direction of rotation of adjustment screw (1): 

Fig 7: Tightening Adjusting Screw On Door Lock

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Checking unlocking of rotary striker lock: 

• Close rotary striker lock (1) with a screwdriver,
• lock car with car key,
• unlock car with car key,
• open rotary striker lock (1) with outside door handle,
• if rotary striker lock (1) opens, then O.K.
• If rotary striker lock (1) fails to open,
• slacken adjustment screw (2) again,
• Retighten adjusting screw (2),
• carry out check again.

Fit sealing cap.

Fig 8: Checking Unlocking Of Rotary Striker Lock

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Checking overtravel at outside handle: 

• Close rotary striker lock with a screwdriver,
• open rotary striker lock with outside door handle (1)
• outside door handle (1) must be able to open further by measurement (A),
• if measurement (A) is obtained, then O.K.
• if measurement (A) is not obtained, readjust rotary striker lock and carry out overtravel check,
• if measurement (A) is still not obtained, you must Bowden cable with carrier.
  Fig 9: Checking Overtravel At Outside Handle

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A min. 2 mm

Replacement only:

Lift out lock (1) and detach Bowden cable (2) from fixture (3).

Remove Bowden cable nipple (4) from lever (5).

Fig 10: Removing Bowden Cable Nipple From Lever

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Replacement only:

Turn linkage for locking knob (1) and detach from lever (2).

Fig 11: Turning Linkage For Locking Knob And Detach From Lever

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Installation: 

Following parts must not be damaged:

1. Spring
2. Mount for Bowden cable of inside door handle
3. Mount for linkage of locking knob
4. Mount for paddle of lock barrel (driver's side only)

The illustration shows the left driver's door lock on the coupe.

Fig 12: Identifying Left Driver'S Door Lock On Coupe

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