Flashing red = car is pointed away from you Flashing yellow = car is pointed towards you It's the same reason why headlights are white and taillights are not

Flashing red = car is pointed away from you Flashing yellow = car is pointed towards you It's the same reason why headlights are white and taillights are not (unless reversing, in which case the tail becomes the head temporarily, and thus white reversing lights.)