What do you mean "trouble"?
I mean, if you're lying to your visitor, then you'll probably eventually get in trouble by the fact that if you weren't "seen on tv" you're just a liar. Things get around the web pretty quick.
Also, yes, you could probably face suit by the media outlet that you're stating covered your site. Might be as simple as a slap on the wrist, or as bad as a fully on suit for slander and / or worse.
All things considered, most times I see a "as seen on..." they feature a link to the video or clip where it was featured. If you don't have that link, there's really no point, and I don't think it'll give you much of a credibility boost.
Edit: oh yeah, you might be pulled from ad networks as well - many of them would consider something like that unethical marketing practices and just pull you.