Where do I plug this antenna adapter?

But the wire looks like connector type adapter, is your intention to have a wired FM modulator? That should get connected between the FM tuner and the antenna, if this device is using the old type connector, you may need more adapters back and forth.

As far as I know, your car (I assume it is equipped with COMAND) would have the FM tuner at the front, integrated to the COMAND display unit. This means that the radio aerial would also go to the front of the car.
In this case you should access the rear of the Comand unit and connect the iPod wired FM adapter there.
Euro cars usually have the 90 degree angled connector shown on your photo. One of your adapters would fit to the rear of the Comand when you remove the FM antenna coax. The FM modulator would probably fit to the other end of the wire (going to Comand) but I'm not sure if your adapter fits the connector from the FM modulator to the car antenna coax. Should be easy to find an appropriate adapter if needed.
I just checked the aerial cable for a car that does not have Comand but a standard radio head unit. It would equally have the aerial at the front of the car.
Note that there are two coax cables, a smaller connector would be for other purposes, the one that fits your 90 degree angled connector would be the correct one to use.
By the way, I assume your car actually has a D2B based fibre system, MOST came a bit later (but would not make any difference in this context).
http://www.oemautointegration.com/product/fmrds-usb-pro
Thanks,



