Hello,
I bought second hand BMW imported from Japan. It has a AUX cable hanging in back central console and the cable is running through it. Can somebody please tell me what it is for?
Thank you

 

That is for plugging in a device that will play music such as your phone, an iPod or MP3 player through your car's speakers without wires hanging around. I'm guessing that the other end is in your console?

 

I wonder if someone either has a bluetooth module hidden in the center console that plays in the car via the aux in port, or, that cable goes into the center console to plug into a phone to play music through aux in and the previous owner didn't want to have the cord dangling about in the car.

 

We never heard back from the OP, so I guess we'll never know.