Removing horns 2007 volvo s80 3.2 - Volvo Cars & Trucks

Not too hard. You pop the grille out, which if it is like the S60 and V70, you pop out the reusable plastic rivets on the slam panel under the hood, bend the plastic forward, reach your hand in and push the grille out (or push on the tabs to release it and then push it out).
Then you can access the horns from the front.

It's doubtful the horns are bad, if that's why you want to get to them, but test them with 12v and see.

If they're not working right, it's possible that your alarm module is bad - but that would be another thing to try once you've determine the horns are good.