When lane-use control signals are placed over individual lanes of a street or highway, these signals shall indicate and apply to drivers of vehicles and trackless trolleys as follows:
(A) A steady downward green arrow. Vehicular traffic may travel in any lane over which a green arrow signal is shown.
(B) A steady yellow X. Vehicular traffic is warned to vacate in a safe manner any lane over which such signal is shown to avoid occupying that lane when a steady red X signal is shown.
(C) A flashing yellow X. Vehicular traffic may use with proper caution any lane over which this signal is shown for only the purpose of making a left turn.
(D) A steady red X. Vehicular traffic shall not enter or travel in any lane over which this signal is shown.
(R.C. § 4511.131) ('81 Code § 70.12)