BMW E90 Door Lock Assembly Replacement 325i 325xi 330i 330xi 335i 335xi

In this article I will show you how to replace the door lock mechanism on a 4 door BMW E90.  The door lock actuator is no longer a separate part that can be replaced so the entire door lock mechanism needs to be replaced if the actuator has stopped working. This project was done on a 2006 325i but the procedure should be the same on any 4 door E90 325i, 328i, 328xi, 330i, 330xi, 335i or 335xi.  This write up can also be used if you are replacing a window regulator.  

1.  Start out by removing the door panel.  Remove the decorative trim and under the trim you will find screws that hold the door panel to the door frame.  You might want to get some spare clips for the trim, sometimes the original clips get damaged.  

2.  The door panel is held to the door frame with clips.  Gently unclip the door panel from the door, some clips will probably brake so you might want to order a few spare door panel clips.  Once the door panel is partially off unclip the door handle cable, disconnect the speaker harness and the door window switch.

3.  Disconnect the door lock harness, the door handle cable and the door lock rod.

4.  Gently peel back the vapor barrier.

5.  Disconnect the window glass from the regulator.  You will need to reconnect the window switch and lower the window just enough to access the clip that holds the glass to the regulator through an access hole in the regulator.  Use a screw driver to push on the clip through an access hole to unclip the glass.  Be careful not to brake the glass.

6.  Remove the glass.

7.  It is kind of hard to see in this picture but you will need to reach inside the door and unclip the door handle cable from the door lock mechanism.

8.  Unbolt the rear window regulator rail and move it out of the way.

9.  Remove the cover plug marked with a red arrow.  Under the cover you will find a screw that needs to be removed in order to remove the door lock cylinder.

10.  Use two old credit cards and a screw driver to pop the lock cylinder out of the door lock mechanism.

11.  This picture shows you the back part of the lock cylinder that clips into the door lock mechanism.

12.  Remove the screws for the door lock mechanism.  Take the door lock mechanism out of the door and install the new one.  Reassemble everything in the reverse order.  Replace the fuses if any are blown.