I had the same question when I bought my '06. Unfortunately, Ford got a little ahead of themselves in the debut year, and although the button is there, it serves no purpose as the car has no auxillary jack or anything on the back of the deck to hook one up. I ended up installing a Sony double DIN aftermarket deck with a front Aux jack and had USB run to the glove box. You'll also need an adapter to hook up the steering wheel controls.