My Super Nintendo/SNES Isn't Working On My Vizio Flat Screen?

Okay, I've Done My Homework.. Everything Is Working, I Have The Power Plugged In, The AC Cord Is Connected To The Cable Cord And The TV Is Tuned To Cable, I've Searched Everywhere On The TV.. Nothing! I'll Have The Channel On 4, Flip The Power On, Goes Good.. Just Black, And A No Signal Shows Up, I've Changed Games So It's Not In The Clean Cartridge File, Everything Is How It's Suppose To Be, Just NO Picture Or Audio, Help! My Flat Screen Is A 32 Inch Vizio LCD 1080p That's All I Know... PLEASE HELP, Trying To Be Cute For A Girl And Kick Her Butt In DK! lol