52 13... Removing and installing/replacing guide for front left or right head restraint

Remove rear panel on front seat backrest:

Guide for head restraint with pushbutton:

Release catches (1) and (2) and slide guide (3) upwards.

Fig 1: Releasing Catches & Sliding Guide Upwards (Guide For Head Restraint With Pushbutton)

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Pull guide (1) out of backrest (2).

Fig 2: Pulling Guide Out Of Backrest

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Installation:

Catches (1) and (2) on guide (3) must not be damaged.
Check that pushbutton (4) works properly.
After installing guide (3), make sure it is properly seated.

Fig 3: Installing Guide
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Guide for head restraint without pushbutton:

Release catches (1) and slide guide (2) upwards.

Fig 4: Releasing Catches & Sliding Guide Upwards (Guide For Head Restraint Without Pushbutton)

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Pull guide (1) out of backrest (2).

Fig 5: Pulling Guide Out Of Backrest

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Installation:

Catch (1) on guide (2) must not be damaged.
After installing guide (2), make sure it is properly seated.

Fig 6: Installing Guide
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