The WD Passports rely on the short USB cable to draw enough power for the hard drive. If you try to connect it to your PC with a longer USB cable you will find out that it won't work due to increased resistance in the cable and not enough power for the drive to spin up, it only clicks. In our case with the F series the unit alredy comes with a pretty long usb cable wich limits the power down. If you hook up an external power for your drive and then hook it up to the AVIC it should work. I have not tried it yet because I just installed my unit and have not played enough with it, but I am pretty