Originally Posted by TerminatorX5

41. Installed a home made AUX cable as I was too cheap to pay $60 for 3 wires...

parts

61136931929 - the 3-pin connector, about $1.75 from BMW of Fairfax

61130006664 - male pin, comes with about a foot of brown wire attached from a dealer, I use a Digi-Key part (to be inserted)

radio shack part 274-246, about $3, the 3.5 stereo input jack

one 300 KOhm resistor, 1/4 watt is good

two 20 nF capacitors

3 pieces of 20-24 gauge wire - i used black for ground (factory color is brown), red for right and white for left audio channels...

the resistor and the capacitors are the components that will tell the car that the AUX input should be activated -

you will need to solder the resistor between the red and white wire, in parallel, and then, after the resistor connection, closer to the jack, solder the capacitors in series in red and white line individually - one capacitor for the red and one for the white lines... the black wire will be the only one that runs uninterrupted...

I will post the wiring diagram once i get to it... but in verbal description, the resistor is used by the car's stereo system to detect the AUX input (load of 300 KOhm) and the capacitors are used to isolate that resistor from the audio equipment that will be plugged into the jack... very simple...

In my case, I run the wire to the central console, and it is mounted in the tray that held the CDs ( i have the CD brackets removed for another project)