Guide for head restraint with pushbutton:

WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 2006 BMW 325Ci, 2005 BMW 325xi, 2005 BMW 325i, 2005 BMW 325Ci, and 2004 BMW 325xi. However, it is still accessible from the selected car via links, so may be relevant.

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

Fig 1: Releasing catches

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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.

Fig 3: Checking Guide

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Check that pushbutton (4) works properly.
After installing guide (3), make sure it is properly seated.