75 Pa. C. S. § 3112. Traffic-control signals

  (a) GENERAL RULE.-- 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 a word legend, and the lights shall indicate and apply to drivers of vehicles and pedestrians as follows:

(1) GREEN INDICATION.--
 
     (i) Vehicular traffic facing a circular green signal may proceed straight through or turn right or left unless a sign at such place prohibits either such turn except that 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.
 
     (ii) Vehicular traffic facing a green arrow signal, shown alone or in combination with another indication, may 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.
 
     (iii) Unless otherwise directed by a pedestrian-control signal as provided in section 3113 (relating to pedestrian-control signals), pedestrians facing any green signal may proceed across the roadway within a crosswalk.

(2) STEADY YELLOW INDICATION.--
 
     (i) Vehicular traffic facing a steady yellow signal is thereby warned that the related green indication is being terminated or that a red indication will be exhibited immediately thereafter.
 
     (ii) Unless otherwise directed by a pedestrian-control signal as provided in section 3113, pedestrians facing a steady yellow signal 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. (3) STEADY RED INDICATION.--
 
     (i) Vehicular traffic facing a steady red signal alone shall stop at a clearly marked stop line, or 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 subparagraph  (ii).
 
     (ii) Unless signing is in place prohibiting a turn, vehicular traffic facing a steady red signal may enter the intersection to turn right, or to turn left from a one-way highway onto a one-way highway after stopping as required by subparagraph (i). Such vehicular traffic shall yield the right-of-way to pedestrians lawfully within an adjacent crosswalk and to other traffic lawfully using the  intersection.
 
     (iii) Unless otherwise directed by a pedestrian-control signal as  provided in section 3113, pedestrians facing a steady red signal alone shall not enter the roadway.
 
   (b) PLACES OTHER THAN INTERSECTIONS.-- 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 such sign or marking the stop shall be made at the signal.
 
   (c) INOPERABLE OR MALFUNCTIONING SIGNAL.-- If a traffic-control signal is out of operation or is not functioning properly, vehicular traffic facing a:
 
   (1) Green or yellow signal may proceed with caution as indicated in subsection (a)(1) and (2).
 
   (2) Red or completely unlighted signal shall stop in the same manner as at a stop sign, and the right to proceed shall be subject to the rules applicable after making a stop at a stop sign as provided in section 3323 (relating to stop signs and yield signs).