I couldn't find a DIY with pictures for this so I took pictures while I did mine. I really like how on the M2 the open pore dry carbon fiber trim on the steering wheel really ties together the whole interior and it does it right in front of the driver, the most important place.
You need a 10 mm ratchet, 20 torx (T20), and a flathead screwdriver that's on the slimmer side.
I used this post as a guide but the pictures are gone.
http://f80.bimmerpost.com/forums/sho....php?t=1066795
Here it is installed.
This is the piece resting unfortunately on my lap, sorry. Part # 32302413480 Some other places make non OEM version with no logo but only gloss CF. You can get the light gray interior trim piece in CF too or some other color.
We don't want the airbag to blow up in our face so we are going to unhook the negative side of the battery. That means you won't be able to open the trunk once the car has no power. Open your car door, open your trunk, then unlatch the the back seats so they fold down. Now if you lock the trunk later you can crawl in through the back seat if needed.
Pull up the floor of the trunk to get at the battery. You want to unhook the NEGATIVE side with a 10mm socket. It's on the right side of the battery, it's clearly marked. I used a cloth to keep the wire from swinging back into the negative terminal once it was off because it wants swing back over that way. Don't unhook the positive side! Don't fucking close the trunk!
Then hang out and wait however long you think you need to before you safely remove the airbag. I waited 20 minutes. I played Mario while I waited.
When you're ready get a flathead screwdriver and put it through the hole on the left side of the steering wheel. I found I needed to aim it slightly angled down and push in and down. You will feel the spring push in and stop. I held it there with my knee and then pulled the left side of the airbag out.
Now do the same for the hole on the right side. If everything goes right then you will be able to pull the airbag off and it won't explode in your face costing you money and self injury. Now you can see those springs you were pushing in that are between the black gaps.
Unplug the airbag by disconnecting the single connector from the hub. I believe there was a tab on the top you need to press down to pull the tab out. No picture for this. You will have to use theater of the mind!
Use the Torx 20 to unscrew the two screws on the front holding the trim into place. Then unscrew the last screw holding the trim in place on the bottom behind the wheel. Ignore that in the pictures I foolishly still have the airbag connected.
Now pull the old and busted trim up and out. Be careful that nothing important is stuck on the back of the trim when it comes off. For me there was a piece of foam that came up with it. Put that back where it belongs...
Now install your new trim! Pretty much the reverse of what you just did. I lined up the bottom and then put the trim in and it easily snapped into place. I took a moment to make sure that the tabs on the top and the bottom of the airbag cavity all fit the way they should. Everything seemed snug so go ahead and screw in the two front screws, then the one on the back of the wheel.
Now clip the airbag wire back in. I didn't have any issue with this, just put it back in and make sure it's snug. Should only go in one way and I can only assume the car will let you know if you did this wrong when you turn it on....
You can see on the back of the airbag there are two prongs that match those two holes where you can see the spring. Just firmly with your hands on both the left and right side of the airbag push it back in. You should feel a bit of resistance from the spring but it should be easy.
Now you're almost finished! Look at that!
Now go back and put the battery wiring back on the negative terminal. It's going to spark a little. Now I have heard it would be smart to turn your headlights on before you do this so a portion of the power is directed to the lights and doesn't fry the computers or anything. I didn't do this. I really don't know what the true risks are here. Thread on disconnecting and reconnecting battery and possible issues here. Long story short though no one had any issue.
http://www.e90post.com/forums/showthread.php?t=536112
Okay now it's time to turn the car on and see if disaster strikes. Move your face out of the way of the airbag.... lol.
Oh look at this, notification on my iDrive. What could it be? Car factory reset? Nope. Just wants the time and date manually set. I think just the time actually.
That's it. You're done!