Factual error: A secret file is password-protected on a computer, requiring a six-digit numerical access code. KITT states that the possibilities "are virtually unlimited." In truth, if each digit can be 0 through 9 (numerical meaning no letters or symbols), the possibility is 1 in 10^6, or 1 in a million. A supercomputer like KITT should have no problem running each number systematically until a correct code is found.
Factual error: The forces of Cassiopeia all sport the crown-like "W" sign which is the shape of that constellation... but only as seen from earth! These five points in three-dimensional space (like all star signs named after anything) look like that when viewed from our own planet; but from anywhere else, they aren't shaped like that at all. Why would they chose to see themselves through a very specific angle of view from some other distant planet (earth)?