Whenever traffic is controlled by traffic-control signals exhibiting different colored lights or color lighted arrows successively one at a time or in combination, only the colors green, red, and yellow shall be used, except for special pedestrian signals carrying a word legend, and the lights shall indicate and apply to drivers of vehicles and pedestrians as follows:
(A) Green indication.
(1) Vehicular traffic facing a circular green signal may proceed straight through or turn right or left unless a sign at such place prohibits either turn. Vehicular traffic, including vehicles turning right or left, shall yield the right-of-way to other vehicles and to pedestrians lawfully within the intersection or an adjacent crosswalk at the time the signal is exhibited.
(2) Vehicular traffic facing a green arrow signal shown alone or in combination with another indication, may cautiously enter the intersection only to make the movement indicated by the arrow, or such other movement as is permitted by other indications shown at the same time. Such vehicular traffic shall yield the right-of-way to pedestrians lawfully within an adjacent crosswalk and to other traffic lawfully using the intersection.
(3) Unless otherwise directed by a pedestrian-control signal, as provided in § 70.12, pedestrians facing any green signal, except when the sole green signal is a turn arrow, may proceed across the roadway within any marked or unmarked crosswalk.
(B) Steady yellow indication.
(1) Vehicular traffic facing a steady circular yellow or yellow arrow signal is thereby warned that the related green movement is being terminated or that a red indication will be exhibited immediately thereafter.
(2) Pedestrians facing a steady circular yellow or yellow arrow signal, unless otherwise directed by a pedestrian-control signal as provided in § 70.12, are thereby advised that there is insufficient time to cross the roadway before a red indication is shown, and no pedestrian shall then start to cross the roadway.
(C) Flashing yellow arrow indication.
(1) Vehicular traffic facing a flashing yellow arrow indication may cautiously enter the intersection only to make the movement indicated by the arrow and shall yield the right-of-way to other vehicles and pedestrians lawfully within the intersection or an adjacent crosswalk at the time the signal is exhibited.
(2) Pedestrians facing a flashing yellow arrow indication, unless otherwise directed by a pedestrian-control signal as provided in § 70.12, may proceed across the roadway within any marked or unmarked crosswalk that crosses the lane or lanes used to depart the intersection by traffic controlled by the flashing yellow arrow indication. Pedestrians shall yield the right-of-way to vehicles lawfully within the intersection at the time that the flashing yellow signal indication is first displayed.
(D) Steady red indication.
(1) Except as provided in division (D)(3) of this section, vehicular traffic facing a steady circular red signal alone shall stop at a clearly marked stop line; but if there is no stop line, before entering the crosswalk on the near side of the intersection; or if there is no crosswalk, then before entering the intersection; and shall remain standing until an indication to proceed is shown.
(2) Except as provided in division (D)(3) of this section, vehicular traffic facing a steady red arrow signal shall not enter the intersection to make the movement indicated by the arrow and, unless entering the intersection to make a movement permitted by another signal, shall stop at a clearly marked stop line; but if there is no stop line, before entering the crosswalk on the near side of the intersection; or if there is no crosswalk, then before entering the intersection; and shall remain standing until an indication permitting the movement indicated by the red arrow is shown.
(3) Except when a sign is in place prohibiting a turn, and local authorities by ordinance or state authorities by rule or regulation prohibit any such turn, vehicular traffic facing any steady red signal may cautiously enter the intersection to turn right, or to turn left from a one-way street into a one-way street, after stopping as required by division (D)(1) or (D)(2) of this section. After stopping, the driver shall yield the right-of-way to any vehicle in the intersection or approaching on another roadway so closely as to constitute an immediate hazard during the time the driver is moving across or within the intersection or junction or roadways. The driver shall yield the right-of-way to pedestrians within the intersection or an adjacent crosswalk.
(3.5) In municipalities with less than 2,000,000 inhabitants, after stopping as required by division (D)(1) or (D)(2) of this section, the driver of a motorcycle or bicycle, facing a steady red signal which fails to change to a green signal within a reasonable period of time not less than 120 seconds because of a signal malfunction or because the signal has failed to detect the arrival of the motorcycle or bicycle due to the vehicle's size or weight, shall have the right to proceed, after yielding the right-of-way to oncoming traffic facing a green signal, subject to the rules applicable after making a stop at a stop sign as required by § 72.32.
(4) Unless otherwise directed by a pedestrian-control signal as provided in § 70.12, pedestrians facing a steady circular red or red arrow signal alone shall not enter the roadway.
(E) In the event an official traffic-control signal is erected and maintained at a place other than an intersection, the provisions of this section shall be applicable except as to provisions which by their nature can have no application. Any stop required shall be at a traffic sign or a marking on the pavement indicating where the stop shall be made, or in the absence of the sign or marking, the stop shall be made at the signal.
(F) The motorman of any streetcar shall obey the above signals as applicable to vehicles.
(ILCS Ch. 625, Act 5, § 11-306) Penalty, see § 70.99