Step 3
remove upper/lower steering column trim to access some wiring behind the coil spring cartridge (aka: slip ring)
(DIY/Pics from doba_s DIY)
"Pull the upper part first. Pull it up and do one side at a time.
You can use a medium size flathead screwdriver and push it up from the inside, but be very careful "
"Remove the lower part by pressing on the tabs (one on each side)"
Behind the coil spring cartridge you should see 2 wire connections
Remove the one closest to the center that have the lock (2nd pic below) and remove it from its casing
depending on your car year/model/options...etc; this connector might have 2 empty pin slots (pin #2 & 4) or you might have 2 yellow wires in pin #2&4.
If you have empty pin slots, then insert 2 wires you made with the pin connectors (these 2 wires will need to be approx. 2.5 feet long).
If you have 2 yellow wires in pin #2&4, then remove the pins and follow above. Make sure to tape up the unused pins of the yellow wires and secure them.
Pic 1 has the empty pin slots
Pic 2 has the 2 yellow wires
Now the other end of these 2 wires will run to the center console, this part is very easy.
Follow Mr. 5 DIY link on how to remove the center console trim
http://www.e90post.com/forums/showthread.php?t=137527
Then, remove the lower part near the gas pedal area (see pic) and run your wires inside there to the center console.
These 2 pics shows where the wires go, you'll see a small gap in between where the arrows point to. Simply slide your wire in between this gap.
Again, the 2 wires from behind the spring cartridge runs to the center console.
You should tape up the wires so that it doesn't hang all over the place, I run the wiring following the oem wires of the steering wheel that are tie to the column and then run it thru where the small gap as describe above.
and now the final part of wiring...
The end of the 2 wires will be connected to the blue connectors under the gear selector, from here we need to tap into the 2 middle wires of the blue connector.
(below pic shows the blue connector)
Now follow AlanIOW's diagram and his direction
"The easy way would be to use scotch clips to the 2 central wire or even just push the wires into the back of either blue connector."
("Ignore the wire colours in my diagrams they are all a bit random")
This is it.....put everything back together but I'll recommend leaving the center console trim open till you have fully tested the paddle shifting.
some notes:
my car is an early 2006 built and I can only shift while in DS mode, but most ppl can shift even in D mode.
I guess it depends on the programing and/or when your car is built....will update this DIY if anything changes