Whenever traffic is controlled by traffic-control signals exhibiting different colored lights, or colored 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 words or symbols, and these 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 the place prohibits either turn. But vehicular traffic, including vehicles turning right or left, 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) 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. The 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 § 70.24, 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 when vehicular traffic shall not enter the intersection.
(2) Pedestrians facing a steady circular yellow or yellow arrow signal, unless otherwise directed by a pedestrian-control signal as provided in § 70.24, 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) Steady red indication.
(1) Vehicular traffic facing a steady red signal alone shall stop at a clearly marked stop line, but if none, before entering the crosswalk on the near side of the intersection, or if none, then before entering the intersection, and shall remain standing until an indication to proceed is shown except as provided in divisions (C) (2) and (3) of this section.
(2) Unless a sign is in place prohibiting a right turn as provided in division (C) (5) of this section, vehicular traffic facing a steady red signal may cautiously enter the intersection to make a right turn after stopping as required by division (C) (1) of this section. 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 a sign is in place prohibiting a left turn as provided in division (C) (5) of this section, vehicular traffic, streetcars, and trackless trolleys facing a steady red signal on a one-way street that intersects another one-way street on which traffic moves to the left may cautiously enter the intersection to make a left turn into the one-way street after stopping as required by division (C) (1) of this section, and yielding the right-of-way to pedestrians lawfully within an adjacent crosswalk and to other traffic lawfully using the intersection.
(4) Unless otherwise directed by a pedestrian-control signal as provided in § 70.24, pedestrians facing a steady red signal alone shall not enter the roadway.
(5) Local authorities may by ordinance, or the director of transportation on state highways may, prohibit a right or a left turn against a steady red signal at any intersection, which shall be effective when signs giving notice thereof are posted at the intersection.
(D) 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 those provisions which by their nature can have no application. Any stop required shall be made at a sign or marking on the pavement indicating where the stop shall be made, but, in the absence of any sign or marking, the stop shall be made at the signal.
(R.C. § 4511.13) ('81 Code § 70.11)