I have 2005 accord ex v6 coupe. Cruise control and horn do not work. Honda
Service advisor said those problems are from airbag. Can anybody tell me the costs for new airbag and repair cruise control approximately?

 

he is probably referring to the the clock spring or some may call it the "spiral cable", in any event, the bag itself will not need replacement and the cruise and horn should be restored as well. worst case, 150 parts/couple hours labor at whatever rate they charge.

to answer your next question, the horn and cruise circuits are integral to the airbag clockspring, that be why they ain'ts working