Re: E90 Car door lock problem
Found some pix I took on my iPhone so here's the resources I used to get this job done on Sun.
This is the guide I used, the pic within was immensely useful.
DIY: Front door lock actuator replacement (E90) - BMW 3-Series (E90 E92) Forum - E90Post.com
Bought the trim removal tool from autobacs ($20) to avoid scratching the door pieces.
The 3 screw holding the door actuator need a "star shaped" torx bit that fit the screw head snugly as you need a lot of torque to remove it. I used a screwdriver type, in hindsight a torque wrench type would make this much easier to remove.
Steps in order:
1) pry out silver long decorative trim below arm rest from door panel w/ trim remover;
2) unscrew 3 long screws underneath arm rest w torx screw driver
3) wind window fully up;
4) pry out entire door panel w/ trim remover tool;
5) unplug speaker power connector, power window connector, door actuator connector and, pull handle wire cable,
6) remove half of moisture sealing barrier (black screen on door inside) via pen knife to cut open black bitumen glue holding it to the edges, exposing the right hand side access holes only to door recess area (no need remove whole thing);
7) loosen sufficiently the top nut (top blue arrow), but not entirely and remove bottom nut (bottom blue arrow) holding silver wire / window guide rails (this is so your left hand can press the bottom to give enough space to twist and squeeze faulty door actuator part out with your right hand through the bottom hole);
8) stick left hand into door actuator area w right hand holding torch light and decouple the door lock cable from within the door recess area (pic is in e90post above);
9) remove round smaller rubber bump near door handle, use allen key to unscrew counterclockwise the retaining screw (see red arrow in pix below) holding key lock (do not unscrew until it falls out entirely, just enough to pull out locking key unit)!
10) tug and pull out entire key lock unit (part where you insert your car key)
Note the retaining pin (orange arrow), do now unscrew from the other end all the way with allen key in case this screw falls out
11) remove door lock wire (black tip that protrude from your door frame head which connects to door actuator motor mechanism)! Mine actually broke here, it's a white plastic piece very fragile but you can twist the wire piece 45' (there's a notch in the plastic piece to allow u to do that) then pull out the wire thing, keep aside
Note: Door lock wire visible here (top orange arrow), still attached to actuator unit (bottom orange arrow)
12) unscrew the 3 black screws holding door actuator to door (blue arrows)
13) now with door actuator loose in the door internals, you need to push and bend the bottom part of window rail guide in and try to rotate the door actuator part out from the access hole (I got it out within 60sec)
14) with the defective door actuator removed, squeeze the new unit in the same way you took old one out, got it in faster than getting the old one out;
Note the old (left) and new (right) actuator, the yellow part (purple arrow) on the old actuator is the plastic clip that holds the other end of the door lock wire, which has broken off. The same white plastic part (see purple arrow, also visible in new actuator) same location is intact.
15) reinstall and connect everything to door actuator is in reverse from here-on
I took my time so manage to get everything done w/o breaking anything and not a scratch. Also, compare and study your new actuator how it connects to the different parts as the view inside door recess area very small and hard to see. You have to squint then work with feeling your way and a bit of visibility.
Unlike in the e90post, there's no need to wide down the window 4-5" I left it up all the time no problem at all.
Also no need to disconnect the battery or do any car computer update, door lock works once new part swap in.
Relatively easy job if you have some technical skills and patience to work on your car for 2 hours to get this fixed yourself.
