This write up is basically tommiexboi's write up and all the people that contributed to tommiexboi's write up, but with a few more pictures. This is a very doable DIY. It is not a quick DIY, but it is not a hard DIY. I am a female who has never worked on a car before (I have never changed a light bulb) and I have now done two of these repairs (driver's side window and front passenger's side window). There are so many reasons why you should do this repair yourself. First, is the cost. A repair shop will charge you anywhere from $250 to $400. Second, if you read through all the window regulator posts you will read enough horror stories that should convince you to do this yourself. Things do not get reconnected properly, vapor barriers are carelessly torn, etc. Having said all this, let me also say that if you follow this DIY and mess something up, I cannot be held responsible.
Let me start by saying, don't run out and buy a new regulator. Save yourself the $75. The first time I did the driver's side window, I bought the new part and then I came across this website and realized that I didn't need to. A simple zip tie modification would have made my old regulator as good as new:
http://www.skene.org/bmw/window/
The caveat to this is that the zip tie modification is not going to work for everyone and the problem is that you will not know if it will work for you until you open up the door, pull out the regulator and look at it. On the regulator there is a small metal cylinder that is connected to metal wire. This cylinder sits in a metal and plastic bracket. Over time, the plastic starts to chip away and the cylinder will pop out. Once this happens, your window will either move up or down very slowly or not move at all. In addition to the slow moving window, you will hear very scary grinding and clicking. There are several places where the regulator can fail. But, if I had to guess, I would say the most of regulators fail around the small metal cylinder. In my situation, both my regulators were failing in this spot. If the failure occurs around the small metal cylinder, then the zip tie modification will work for you. Here is what one of my metal and plastic brackets looked like. The cylinder sits in the space that I labeled "cylinder". You can see where the plastic broke off exposing the metal underneath:
<img src="http://www.E46Fanatics.com/images/forum/regulator19.jpg">
Now onto the actual repair. Before you start this is what you will need. Do not attempt to start this repair without having these tools:
<li>1/4" drive ratchet
<li> 1/4" drive ratchet extension (there is one step where you will need a very narrow 8mm socket. A 3/8" drive size will not allow the 8mm socket to fit through the hole.)
<li>Torx t-20
<li>Torx t-30
<li>8mm socket
<li>10mm socket
<li>Screwdriver
<li>At least one ziptie, possibly more</li>
Now let's begin:
1. If you can, roll down the window half way. If the window doesn't move at all don't worry about it. No matter where it is, it will inevitably need to be moved later on.
2. Use your 10mm socket to disconnect the negative battery terminal. On my car the battery is in the trunk on the right side:
<img src="http://www.E46Fanatics.com/images/forum/regulator1.jpg">
3. Use a screw driver to gently pry away the wood trim. Put the trim in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator2.jpg">
4. Underneath the armrest are 2 plastic caps. Pull them out and put them in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator3.jpg">
5. On the armrest you will either have a window control, a side mirror control, or a blank plug. (On my passenger side I have a blank plug). This will need to be removed. On the driver's side I was able to use a screwdriver with a very thin tip to remove it without any problems. On the passenger side, this blank plug was very deep in the hole and the screwdriver was not working. I could see that if I really forced the screwdriver in there it would have damaged the leather. Not really knowing what to do, I started looking around the house for something I could use to get this plug out. I tried this Wustoff carrot peeler and it worked great! No damage to the leather. I think any peeler in this basic shape should do the trick. You might also want to try removing the plug at the other end if you are having trouble. Sometimes removing the plug on the side that is higher up the arm is a little easier. If you have a window control or a mirror control in this spot, once you get it out disconnect the wires that are attached to it. Put the control in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator4.jpg">
6. Remove the 5 torx t-20 screws that are circled in red:
<img src="http://www.E46Fanatics.com/images/forum/regulator5.jpg">
7. You are now ready to pry off the door panel. There are these white plastic protrusions on the door panel that snap into the door. You can't see them at this point, but these protrusions are holding the door panel to the door. They are spaced all around the door panel except for the top of the door. There are also a few around the large speaker. The best place to start prying is where the screwdriver is pictured. Gently wedge your fingers or a screwdriver into this spot and gently pry that corner of the door panel away from the door. If you can use your fingers it will be better than using a screwdriver because it is less likely that you will damage the leather. Once you hear the first pop, stop prying so that you can readjust your fingers. If you used a screwdriver to start prying off the door panel, put it down, you will not need it anymore. At this point you have created enough space for your fingers to pry the rest of the door off. I found the best way to finish prying the door panel off the door is to move clockwise down the door:
<img src="http://www.E46Fanatics.com/images/forum/regulator6.jpg">
8. Once you get the door panel off, hold onto it and keep it relatively close to the door. Don't let it drop to the floor. There are wires and things attached to the door panel that you will need to disconnect. You will need to disconnect the 3 items circled below. The white piece that is circled is already disconnected in the picture. It is part of door handle and needs to be unhooked. The other two circled items are speaker wires that need to be unplugged. The arrows point to these small plastic pieces that hold the wires and plug into the door panel. Gently pull them out to free the wires from the door panel. Once everything is unplugged, let the wires hang and put the door panel in a clean safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator7.jpg">
9. It's now time to remove the airbag. Use the 10mm socket to remove the 3 bolts:
<img src="http://www.E46Fanatics.com/images/forum/regulator8.jpg">
10. Hang the airbag up and out of the way. The best thing to use is a ziptie, but I didn't have one that was long enough, so I just used some strong twine:
<img src="http://www.E46Fanatics.com/images/forum/regulator9.jpg">
Let me start by saying, don't run out and buy a new regulator. Save yourself the $75. The first time I did the driver's side window, I bought the new part and then I came across this website and realized that I didn't need to. A simple zip tie modification would have made my old regulator as good as new:
http://www.skene.org/bmw/window/
The caveat to this is that the zip tie modification is not going to work for everyone and the problem is that you will not know if it will work for you until you open up the door, pull out the regulator and look at it. On the regulator there is a small metal cylinder that is connected to metal wire. This cylinder sits in a metal and plastic bracket. Over time, the plastic starts to chip away and the cylinder will pop out. Once this happens, your window will either move up or down very slowly or not move at all. In addition to the slow moving window, you will hear very scary grinding and clicking. There are several places where the regulator can fail. But, if I had to guess, I would say the most of regulators fail around the small metal cylinder. In my situation, both my regulators were failing in this spot. If the failure occurs around the small metal cylinder, then the zip tie modification will work for you. Here is what one of my metal and plastic brackets looked like. The cylinder sits in the space that I labeled "cylinder". You can see where the plastic broke off exposing the metal underneath:
<img src="http://www.E46Fanatics.com/images/forum/regulator19.jpg">
Now onto the actual repair. Before you start this is what you will need. Do not attempt to start this repair without having these tools:
<li>1/4" drive ratchet
<li> 1/4" drive ratchet extension (there is one step where you will need a very narrow 8mm socket. A 3/8" drive size will not allow the 8mm socket to fit through the hole.)
<li>Torx t-20
<li>Torx t-30
<li>8mm socket
<li>10mm socket
<li>Screwdriver
<li>At least one ziptie, possibly more</li>
Now let's begin:
1. If you can, roll down the window half way. If the window doesn't move at all don't worry about it. No matter where it is, it will inevitably need to be moved later on.
2. Use your 10mm socket to disconnect the negative battery terminal. On my car the battery is in the trunk on the right side:
<img src="http://www.E46Fanatics.com/images/forum/regulator1.jpg">
3. Use a screw driver to gently pry away the wood trim. Put the trim in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator2.jpg">
4. Underneath the armrest are 2 plastic caps. Pull them out and put them in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator3.jpg">
5. On the armrest you will either have a window control, a side mirror control, or a blank plug. (On my passenger side I have a blank plug). This will need to be removed. On the driver's side I was able to use a screwdriver with a very thin tip to remove it without any problems. On the passenger side, this blank plug was very deep in the hole and the screwdriver was not working. I could see that if I really forced the screwdriver in there it would have damaged the leather. Not really knowing what to do, I started looking around the house for something I could use to get this plug out. I tried this Wustoff carrot peeler and it worked great! No damage to the leather. I think any peeler in this basic shape should do the trick. You might also want to try removing the plug at the other end if you are having trouble. Sometimes removing the plug on the side that is higher up the arm is a little easier. If you have a window control or a mirror control in this spot, once you get it out disconnect the wires that are attached to it. Put the control in a safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator4.jpg">
6. Remove the 5 torx t-20 screws that are circled in red:
<img src="http://www.E46Fanatics.com/images/forum/regulator5.jpg">
7. You are now ready to pry off the door panel. There are these white plastic protrusions on the door panel that snap into the door. You can't see them at this point, but these protrusions are holding the door panel to the door. They are spaced all around the door panel except for the top of the door. There are also a few around the large speaker. The best place to start prying is where the screwdriver is pictured. Gently wedge your fingers or a screwdriver into this spot and gently pry that corner of the door panel away from the door. If you can use your fingers it will be better than using a screwdriver because it is less likely that you will damage the leather. Once you hear the first pop, stop prying so that you can readjust your fingers. If you used a screwdriver to start prying off the door panel, put it down, you will not need it anymore. At this point you have created enough space for your fingers to pry the rest of the door off. I found the best way to finish prying the door panel off the door is to move clockwise down the door:
<img src="http://www.E46Fanatics.com/images/forum/regulator6.jpg">
8. Once you get the door panel off, hold onto it and keep it relatively close to the door. Don't let it drop to the floor. There are wires and things attached to the door panel that you will need to disconnect. You will need to disconnect the 3 items circled below. The white piece that is circled is already disconnected in the picture. It is part of door handle and needs to be unhooked. The other two circled items are speaker wires that need to be unplugged. The arrows point to these small plastic pieces that hold the wires and plug into the door panel. Gently pull them out to free the wires from the door panel. Once everything is unplugged, let the wires hang and put the door panel in a clean safe spot:
<img src="http://www.E46Fanatics.com/images/forum/regulator7.jpg">
9. It's now time to remove the airbag. Use the 10mm socket to remove the 3 bolts:
<img src="http://www.E46Fanatics.com/images/forum/regulator8.jpg">
10. Hang the airbag up and out of the way. The best thing to use is a ziptie, but I didn't have one that was long enough, so I just used some strong twine:
<img src="http://www.E46Fanatics.com/images/forum/regulator9.jpg">