[tinkerman]

My 2007 E90 320i driver side door lock actuator needs to be removed. I'm aware that ISTA-D instructs unclipping the rearside window from the regulator & unbolting and laying down the rear window regulator rail in the door, as well as the many DIYs that unbolt the rail's bottom nut while loosening the upper bolt to push forward the rail as an alternative method.

But I'm wondering if it may be possible to remove the actuator without removing the rail at all, and just rotating the actuator on the vertical axis 180 degrees to go around the rail. This is possible on a 2013 328i sedan, as demonstrated in the following video (go to 00:07:46);

Has anyone tried this sort of method of rotating the actuator after unscrewing, then easing around the rail (without having to remove or loosen it) on an E90 (2006-2012)?

[charlie_m]

I just did the drivers door actuator on my 2012 E92 (coupe), and there is definitely *not* room between the regulator and the outer door skin to do this, sorry. Sedans may be different, but I don't think so.

[tinkerman]

Thanks charlie_m for chiming in.

Were you not able to rotate the actuator 180 degrees like in the video?
I'd appreciate any details.

The reason I've got some hope that it might work, is the following DIY YouTube video;
"BMW Door Actuator Fixed E90 2007 3 Series 328I M3"

around 00:04:23 into the video, the actuator is shown rotated at least 90 degrees inside the door (to show the wire clips through the holes in the door chassis).
Although this other DIY also involved loosening the window regulator rail nut(s) for the actual removal, if the actuator can be rotated 90 degrees as in the 2nd video, with even a little wiggle room as it seems, it seems reasonable to assume that it might be possible to rotate the actuator another 90 degrees for a full 180 degrees total (as shown in the 1st video here).

If so, then it would seem possible to go around the upper portion of the window regulator rail while shifting the actuator from a vertical position to a horizontal position to remove it from the upper opening* in the door chassis (* 2007 E90 has slightly different door chassis openings than the 2013).

[charlie_m]

On my 2012 E92, the gap was bigger between the regulator rail and the *inside* door sheet metal than it was between the regulator rail and the *outside* door skin. Yes, I played tetris for a while with it; it was very close to coming out thru the bigger inside gap, but no way was it coming out behind the regulator.

I know there are differences between E90 and E92, and also differences with the LCI update. Maybe yours will be different, but I would plan on moving the regulator.

[tinkerman]

In the Pelican Parts website I found a page of interest;
BMW Parts > BMW E90 3-Series Technical Articles (2006-2011) > BMW Door Latch Replacement
https://www.pelicanparts.com/BMW/tec...eplacement.htm

In the main guide with pictures, there is no mention of removing the window or disconnecting/loosening the window regulator.

Lower in the page, under the 'Comments and Suggestions', on August 18, 2015, 'michvin' comments, "Latch comes out not easily, but it does if flipped vertically and then horizontally. It is tight, but possible. Then it is possible to take it under window rail long flat side first."

This method adds an additional horizontal flip after the initial vertical flip, which I think should help, since leading with the 'long flat side first' going around the rail would reduce the swung 'tail end' and reduce the amount of bumping into the outward door panel, while increasing the leading length of the actuator that can exit the upper opening.

Towards the end of month, when the basement parking lot gets cooler, I'll try this and post my experience.

In the meantime, if anyone tries this, I'd appreciate your input.

[tinkerman]

So on a 2007 E90 sedan, the front (driver side) door lock actuator CANNOT be removed by simply rotating or flipping its position within the door, without partial or entire removal of the rear window regulator rail.

The actuator is "L" shaped, and the distance between the open ends of the "L" shape (think hypotenuse of a triangle) is longer than the distance internally between the door's steel panels(which is only slightly longer than the long side of the original parts actuator). It is possible to rotate the actuator on the vertical axis 90 degrees in one direction (long side first), but trying to rotate another 90 degrees is immediately obstructed, as the 'hypotenuse' length comes into play and bumps the door's panels. This is true no matter how the actuator is flipped or rotated initially (making it impossible to orient the actuator to 'go around the rail'). Removing the white plastic cover on the actuator or even removing the door handle assembly doesn't help either.

Therefore, the window regulator rail (rear one) needs to be either partially or entirely removed from its installed position.

There are many DIY videos online of folks unbolting only the bottom nut and just loosening the top nut (without any clarification of unclipping the window from the plastic clip on the rail) and just pushing the lower section of the rail outward/forward to make room for the actuator to squeeze through the small opening formed by the door panel's lower section hole and the rail's lower section. In such process it is clear that they tearup the the actuator's weather seal (which is bad if one intends to fix and reuse the actuator).

I chose to uninstall the rear side rail and lay it on down inside the door. I had to unclip the window from the rear side plastic clip by lowering the window several inches to access the white plastic clip through one of the rail's holes - I chose the upper one, raising the window shy of a few inches from the top in small steps with the window's rear section still 'riding' the clip(unclipped), then unbolted and carefully disconnected the the rear side window regulator from the window and laid it on the bottom inside the door as advised in ISTA-D. The thinner diagonal regulator cable housing (clipped to the door) has to be unclipped from the door and nudged to a curve (from its straight position) to allow the cables to collapse and the rear side regulator rail to lay down flat in the bottom of the door. With the rear side window regulator rail completely out of the way, the actuator can be removed with ease and without any damage to the actuator's weather seal.

Upon opening up the actuator, I was expecting the larger plastic gear to be broken in some sections and possibly some other plastic lever/arm to be damaged(as I have heard a few times a rattling sound when trying to unlock with the remote - often associated with a damaged gear), but to my utter disbelief I found that no internal plastic components were damaged. WT*?!

The only thing I noticed that may have contributed to issues is that the lubricating grease was pretty thick with some signs of 'grease dry out' (grease losing it's ability to lubricate because the oil separates from the thickener). I took out the main plastic (culprit) parts (larger plastic gear, roughly C-shaped black main (lock/unlock) pivoting lever, and the straight short arm piece) and seeing no damage in any of them, I just cleaned off the old grease from the large gear and applied some silicone grease (paste, NOT spray - sprays have hydrocarbon solvents which cause premature failure of plastic components).

I then mock reinstalled the actuator in the door without connecting the pop-up rod and tested for functionality and found that the actuator lock's but still does NOT unlock with the remote(fob). Manually the actuator functions fine. BTW, all other actuators (other than the driver's side) lock/unlock fine with the remote.

I checked(visually) the door lock related fuses (56, 57 etc.) and none showed obvious damage.

I read some posts online about the need for clearing errors(fault codes) with ISTA-D (diagnostic program) or equilvalent, and also disconnecting the battery's negative lead to reset the car's relevent ECU(s), so I intend to try this next (along with rechecking the fuses with a multimeter).

Has anyone encountered a similar situation (no parts damged internally, only some signs of drying/hardening grease) and perhaps been able to revive the actuator by relubrication and electrical reset? If so, what specific lubricant or solution worked for you?

[charlie_m]

If it locks OK, don't bother checking fuses because it has power to lock. My symptom was opposite, actuator would unlock but not lock. Sorry, I didn't diagnose the broken part, just put the new unit in and moved on.

[tinkerman]

Originally Posted by charlie_m

If it locks OK, don't bother checking fuses because it has power to lock. My symptom was opposite, actuator would unlock but not lock. Sorry, I didn't diagnose the broken part, just put the new unit in and moved on.

Thanks for the pointer on the fuses. That makes sense, that's why I was(and still am) so puzzled.

I think it is highly likely that BMW's mention of a common cause being "silicone contamination" may be the same issue I mentioned regarding '(silicone) grease dry out' (hardening caused by oxidation, silicone oil separation from thickener etc.). This would explain the gradual slow response of some actuators before they malfunction one way or other.

Next chance I get, I'll try clearing fault codes and disconnecting the battery's negative lead to reset any relevant ECU(s) and relay(s) as advised by someone on another forum. If this doesn't fix the issue, I'll get a new unit.