windscreen

Right behind the mirror.

I would think the dealer would be able to help you out. I spent about 15 minutes going through the owner's manual and I found nothing.

I have it behind the mirror but it's not working. Also couldn't find anything in the manual. Have a question out to the dealer, but response, so far, is very slow. Thanks for trying!

Behind the rear view mirror would be the most logical place, but Audi may not be logical in their thinking.

Try contacting the authority that issued your "E-Pass" you may need to get an externally mounted one. Those usually mount at the front license plate holder.

No - I am in Ireland and that is not required. The instructions they have is behind mirror, but clearly there is an issue with the extra thickness of the insulated glass on the Q7 (which they note may be an issue). That, I assume, is why Audi create a "window" in the windscreen. It would just help if they told me where the window is. For example in the A8 it is apparently on the bottom right of the windscreen.

You may have to move it around a bit behind the mirror and up high to get it to work. I did find some info regarding this on Porsche vehicles, but came up empty on Audi.

Found it. I read on another forum a good suggestion. Look at the windscreen in bright light while wearing polaroids. Bingo, there it was. A 6 x 4 inch window, very faint dotted background, about 6 inches to the right of the rear view mirror and 2 inches from the top of the screen. Almost imperceptible without polaroids on. Not sure how you would ever detect it without them. I asked Audi Customer Service AND my retailer, and none of them knew where it was. All of them said the same "behind the mirror". Thanks for trying, but hopefully if anyone else googles this now, they'll find the solution.

Glad you found it and I appreciate your posting the solution here. It might help someone else.