So I'm reading the August, 2004, issue of FHM magazine and I come across "Five things you didn't know about Knight Rider" on page 65. Oddly enough, there is a Battlestar Galactica reference.
KITT was designed by George Barris, the guy who made the original TV Batmobile and the Dukes of Hazzard's General Lee. Show co-creator Glen Larson, who had also created Battlestar Galactica, added the light that blinks when KITT talks. He wanted to mimic the Cylon's red glowing eye.