That's not what I meant. When you connect a USB device, it will appear to the device it is being connected to as whatever the manufacturer intended. If you connect your iPad to a PC without iTunes, all you get is the contents of the photo stream appearing. If your car isn't set up to recognise an apple device, all it will see is the photo memory. If you have iTunes, it will appear as an iPad with all the functionality apple intended
The note may well present as a memory stick, and if the car can see the folder structure of its memory you might be able to play any mp3 files you have stored on it.