(625 ILCS 5/12-210) (from Ch. 95 1/2, par. 12-210)
    Sec. 12-210. Use of head lamps and auxiliary driving lamps. (a) Whenever the driver of any vehicle equipped with an electric driving head lamp, driving head lamps, auxiliary driving lamp or auxiliary driving lamps is within 500 feet of another vehicle approaching from the opposite direction, the driver shall dim or drop such head lamp or head lamps and shall extinguish all auxiliary driving lamps.
    (b) The driver of any vehicle equipped with an electric driving head lamp, head lamps, auxiliary driving lamp or auxiliary driving lamps shall dim or drop such head lamp or head lamps and shall extinguish all auxiliary driving lamps when there is another vehicle traveling in the same direction less than 300 feet to the front of him.
    (c) No vehicle shall have the lighting system modified to allow more than 2 electric head lamps to be lighted while operating in the dimmed or dropped position.
    (d) Nothing in this Section shall prohibit the use of auxiliary driving lamps, commonly referred to as "fog" lamps, when used in conjunction with head lamps, if such auxiliary driving lamps are adjusted and so aimed that the glaring rays are not projected into the eyes of drivers of oncoming vehicles.
(Source: P.A. 85-1144.)