Any body take the steering wheel apart?

[ethermal]

Ok this might just be personal preference but it is driving me nuts. On the left side of the steering wheel is 4 buttons and 4 buttons on the left. Two buttons on the left turn the volume up or down and the other two buttons on the left do exactly nothing. They are for the phone but I didn't buy the blue tooth upgrade nor do I own a phone so those buttons will do nothing forever. On the right side two buttons control next/prev track/radio station which I use a lot. The problem is my right hand is rarely on the steering wheel and my left hand is always on the steering wheel cause I can rest it on the door arm rest and comfortably hold the wheel. So what I would like to do is rewire the button functions so that the next/prev track buttons on the right are programmed to the phone buttons on the left side of the steering wheel. It would be great if this could be done in software but realistically it probably can't be done. So just curious if anyone has taken the steering wheel apart and what does the wiring looking like for the buttons? If it is a straight wiring job then it should be simple for me to simply re-wire the buttons.

[bman6074]

Yea i would like to see this as well.

[AussieRacer]

This is available from e90Post: http://www.e90post.com/forums/showthread.php?t=11825

[kentgbr]

Originally Posted by ethermal

Ok this might just be personal preference but it is driving me nuts. On the left side of the steering wheel is 4 buttons and 4 buttons on the left. Two buttons on the left turn the volume up or down and the other two buttons on the left do exactly nothing. They are for the phone but I didn't buy the blue tooth upgrade nor do I own a phone so those buttons will do nothing forever. On the right side two buttons control next/prev track/radio station which I use a lot. The problem is my right hand is rarely on the steering wheel and my left hand is always on the steering wheel cause I can rest it on the door arm rest and comfortably hold the wheel. So what I would like to do is rewire the button functions so that the next/prev track buttons on the right are programmed to the phone buttons on the left side of the steering wheel. It would be great if this could be done in software but realistically it probably can't be done. So just curious if anyone has taken the steering wheel apart and what does the wiring looking like for the buttons? If it is a straight wiring job then it should be simple for me to simply re-wire the buttons.

I've done some poking around with the 335i switch control modules, I believe they're the same on the 135i. All four functions are brought out on one shared wire per module so it's not practical to rewire two distinct functions from left to right. However, it should be simple to swap all left functions over to the right module and vice-versa. This might work for you if you change tracks more than you change volume.

There is a 6 pin connector that plugs into the wheel assembly from the two switch modules. For my car (step w/paddles) pins 1 and 2 connect to the right and left switch modules respectively. Reversing these removable pins should transfer the left and right functions. I haven't tried this mod myself but I've verified the connections on a spare switch module harness. It's possible a non-paddle shift car might be a little different so YMMV. Even if it was it would be simple to confirm the pinout with a DMM.

[kentgbr]

I 've confirmed that swapping pins 1 and 2 on the steering wheel button control harness does swap the functions as described in my previous post. If anybody has any interest I'll follow up with more details. It's a 5 min job and only requires the airbag to be released and moved aside, not unplugged.

[Brandon26pdx]

I would stongly recommend disconecting the negative terminal on the battery and carefully securing it away from the battery post before removing/handling the airbag in any way. If that thing accidentally goes off you could be in big trouble. (Not to mention they cost a king's ransom.)

Also be super-super careful with the two little wiring harnesses that plug into the back of the airbag if you want to disconnect it and move it aside. Use a tiny flatblade screwdriver to pry up the little retaining clips on the back of the plugs, but you do NOT need to completely remove the retaining clips from the harness to unplug it...they often will break if you try to pry them all the way off. (if you pry them up maybe 1/8 inch they have a natural "stop point" where they dont want to go any further without more force.)

[kentgbr]

Originally Posted by Brandon26pdx

I would stongly recommend disconecting the negative terminal on the battery and carefully securing it away from the battery post before removing/handling the airbag in any way. If that thing accidentally goes off you could be in big trouble. (Not to mention they cost a king's ransom.)

I agree completely. My intention was to confirm feasibility only. People can refer to steering wheel DIY's if they want to go further.

[bman6074]

Can anyone offer photo's of the pins that need to be swapped? And what the pins contorl originaly?
thanks

[kentgbr]

Originally Posted by bman6074

Can anyone offer photo's of the pins that need to be swapped? And what the pins control originally?
thanks

Pin - Function
1) - audio source/recirculation/chan up/chan down
2) - voice activate/phone/vol up/vol down
3) - common
4) - paddle upshift
5) - power (best guess)
6) - paddle downshift

This is a 335 pinout, 135 should be the same but no guarantees. I believe wires to 4 and 6 are not used on non-paddle shift cars.