Join Date: Oct 2002
My Ride: 2002 2.2L I6 Sedan
Complete M3 OEM Mirror Retrofit DIY for e46 Sedan
I felt there was still room in the M3 Sedan mirror retrofit DIYs for a more complete DIY.
I had purchase the M3 Mirrors several months ago, but didn't make the time to install them earlier.
Since my car is 2002 model, no problem about the ribbon wires used in the latter models. And since I didn't want to have autofold mirrors that made everything a little simpler.
As you know with any other DIY your proceeding at your own and sole risk, I'm not liable for anything.
Part 1 - Remove the stock mirrors.
Firs stop, read the e46fanatics Hagus sedan mirror install. HereHere
There you read that you have to remove two little black plugs that hold the black trim that actually covers the sail panel and the tweeter location.
The one thing that I wanted to add to this instructions were the pics of the metallic clip.
Before you start lower your window fully, cause in the final steps for removing the trim you need the window down.
Also, I have included several pics of how the trim looks partially removed from the car so you can see how to better remove it. Look at the edge in this next pic, this edge goes between a rubber seal and the window, that is why it is important to lower the window.
After that, removing the mirror is really straight forward, just remove the filler behind the tweeter and unscrew the 3 screws holding the mirror. Torx 30.
Thats the end of part 1.
Part 2 - Modifying the bases for proper fitment.
As you probably know, the M3 mirror base is a smaller triangle than the stock base. So the leveling and fitment is key to a good installation. On the pro side the hypotenuse of the triangle base is a perfect guide to get a leveled and aligned mirror base.
In my particular case, I read, and marked both bases following the mighty famous Rouge Engineering DIY for the base modification.
But after marking the bases I didn't directly go out and grind the bases as suggested, instead I try fitting the bases before grinding down anything.
The fist thing I did was make a small cut or indentation to the base about 2.5mm, as seen here.
This indentation allowed me to better position the mirror to the metal lip that shows up when you remove the stock mirrors.
What I found out after that is that I needed to cut the hypotenuse of the base as per RE instructions. That part was the only one that I followed to the letter.
One thing I noticed is that I didn't have to grind down the four studs that come with the mirror base. I did have to grind down a small portion of the ones that are located more towards the front of the car when your test fitting the base. These two I had to cut in an angle to clear the shape of the door where the mirror goes. As you can see the door has a little small triangle that points up and bulges out.
For the part about cutting the hypotenuse of the base, I used a rotary tool first with a cut-off disk. But that didn't seemed so good, it worked but was slow and some what difficult to maintain a straight line on the cut. Then I just marked the line with the rotary tool and went on with a manual hacksaw. It proved to be much better since the aluminum base is easier to cut with the hacksaw. Here are a couple of pics.
The cut was so smooth that the hole strip came off as one piece for both bases.
Next, we have to cut a small piece of metal of the door. These piece is a small lip that hides behind the stock base, but with the M3 bases it sits in the way. This lip makes the trim around the window remain flatter. After the cut the trim still sits pretty flat and does not seem to affect in anyway.
For cutting this part I think the rotary is the best tool hands down. Protect the car below and above this area as a precaution. As you can see I used a dull hacksaw blade to go in between the plastic trim and this metal part. With the rotary tool I cut following the blue line. To mark this blue line I first marked where the mirror sat against this metal part, then with that line as reference I drew the blue line about 4mm inside from where the fist pencil line was drawn. This is because the mirror base is pretty think in all it's sides and if the mirror base can't clear this metal part it wont seat flush to the door. As you can see the cut is kind of angled.
When your in the process of drawing this line for the cut, you should have a good idea of how the mirror should fit from all it's sides so the cut is aligned with the fitment your trying to get.
The following pics shows the overall fitment you should be after, maybe you can find a better fitment than what I got, but you get the general idea.
Notice in this pic that there is a barely noticeable very small circle with an X inside. These little mark can be used as reference for the fitting process.
Part 3 - Bolting the M3 mirrors.
When all the back and forth of the fitment process is over, it is time to drill two new holes for the M3 mirror bases. As you seen from the pictures, the M3 mirrors only have preparations for two mounting screws.
What I did and somewhat worked, was cut and file down a small piece off a color pencil or crayon and use it to mark the best I could the location for the the holes to be drilled.
The thing to watch here is that the top hole, at least in my case, is close to the semi-circular opening in the door, and you have to be careful not to make this location too weak to hold firmly the screw and mirror. As it is very likely you have experience drilling challenging holes I'll only recommend to make the fist hole with a small drill bit and see if the location was good or you need to move it. As you can imagine the position of these holes directly affect the fitment of the hole base. You could also make use of a cardboard template of the position of the holes in the base and use it to draw mark the holes on the door.
For the lower screw I made a bit of room for it since it was hitting against the door from the inside a little bit, but could be that in your case this is not needed.
Part 4 - Making the wiring and mirror connection
For the wiring, I used the 5 cables that I had to use for my setup to work, like stated at the beginning I didn't have autofold, ribbon or memory function for my mirrors. So I cut and soldered red to red, gray to gray, green to green, brown to brown, and black to brown. I had two browns so one went with the black wire.
For this part I followed this great DIY: Genuine M3 Mirror Install with Autofold retrofit and 12 to 6 pin conversion on a e46 Coupe. This DIY is very good and has instructions for autofold and 12pin conversions, it covers a little on retaining memory function for the mirrors.
That's the end of part 4.
Right now mirrors are at the body shop waiting for painting. I'll post those pics as soon as I can get them installed.
No, no, there is no climate change, it just getting hotter and hotter....and hotter. Yeah, right!?!!?