I'm not an expert on the 2011, so I'll just tease you with my horn resolution on my 1994 Jeep Grand Cherokee. I was able to replace the horn from underneath, looking up behind the bumper cover. One of the two horns worked so I did minimal diagnostics (perhaps connecting 12 volts directly to the horn to confirm it was dead), then unbolted the old and installed the new.
Look around and see if you can visually see the horn through the bumper cover or from various angles. Sometimes if you can see it, you can remove it without taking off other parts. If you must take off the bumper cover, see if you can get away with removing one side. If it's easy enough, take the cover off and get the job done.