De Wikipedia :
KITT's scanner is similar to that of Cylons from the science fiction series Battlestar Galactica. Glen A. Larson, the creator of both Knight Rider and Battlestar Galactica has stated that the two shows have nothing else in common and to remove any fan speculation, he stated in the Season One Knight Rider DVD audio-comments, that he simply reused the scanning light for KITT because he liked the effect.