51 21 140 Removing and installing/replacing complete lock cylinder in left or right front door

Necessary preliminary tasks:

NOTE: Screw (2) must be outside lock cylinder (1).

Fig 1: Identifying Outside Lock Cylinder

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Release screw (1) until lock cylinder is free.

Fig 2: Releasing Screw Until Lock Cylinder Is Free

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Removal:

Insert ignition key (1) approx. 2/3 into lock cylinder (2).
Turn lock cylinder (2) with vehicle key (1) through 90°.
Pull lock cylinder (2) with ignition key (1) out of lock actuator (3)

Fig 3: Inserting Ignition Key Into Lock Cylinder
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Installation:

Following parts on lock cylinder (4) must not be damaged or missing:

Paddle
Guide
Stop for screw

Fig 4: Locating Parts Of Lock Cylinder
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Installation:

Notch (2) of paddle mount (1) must be secured in catch (3).

Only in this position will installation of the lock barrel be guaranteed.

Fig 5: Ensuring Notch (2) Of Paddle Mount (1) Is Secured In Catch (3)

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