@leojik , Before pulling the steering wheel because your horn does not work, Check all fuses and horn relay and the horn itself. May be bad/corroded ground at the horn. Links below show horn fuse/relay locations, horn location and removal, steering wheel removal to access horns wiring/plug. Check the attached links,instruction and guides, Good luck.
I hope this helped you out, if so let me know by pressing the helpful button.
http://troubleshootmyvehicle.com/honda/1.7L/2005-under-hood-fuse-box
https://www.youtube.com/watch?v=0ra0E0phnXs
https://www.youtube.com/watch?v=d0GHgOChPvU