The City Traffic Engineer shall place and maintain traffic control signs, signals and devices when and as required under the traffic ordinances of this City to make effective provisions of said ordinances and may place and maintain such additional traffic control devices as he may deem necessary to regulate traffic under the traffic ordinances of this City or under State law or to guide or warn traffic.
All traffic control signs, signals and devices shall conform to the manual and specifications approved by the Department of Public Works and Buildings, Division of Highways, State of Illinois. All signs and signals required hereunder for a particular purpose shall so far as practicable be uniform as to type and location throughout the City.
The driver of any vehicle shall obey the instructions of any official traffic control device applicable thereto placed in accordance with the traffic ordinances of this City, unless otherwise directed by a Police Officer, subject to the exceptions granted the driver of an authorized emergency vehicle in this Ordinance.
No provision of this Ordinance for which signs are required shall be enforced against an alleged violator if at the time and place of the alleged violating an official sign is not in proper position and sufficiently legible to be seen by an ordinarily observant person whenever a particular section does not state that signs are required, such section shall be effective even though no signs are erected or in place.
Whenever traffic is controlled by traffic control signals exhibiting different colored lights successively one at a time or with arrows, the following colors only shall be used and said lights shall indicate and apply to drivers of vehicles and pedestrians as follows:
A. 
Green alone.
(1) 
Vehicular traffic facing the signal may proceed straight through or turn right or left unless a sign at such place prohibits either such turn. But vehicular traffic shall yield the right-of-way to other vehicles and to pedestrians lawfully within the intersection at the time such signal is exhibited.
(2) 
Pedestrians facing the signal may proceed across the roadway within any marked or unmarked crosswalk.
B. 
Yellow alone.
(1) 
Vehicular traffic facing the signal shall stop before entering the nearest crosswalk at the intersection, but if such stop cannot be made in safety, a vehicle must be driven cautiously through the intersection.
(2) 
Pedestrians facing such signal are thereby advised that there is insufficient time to cross the roadway, and any pedestrian then starting to cross shall yield the right-of-way to all vehicles.
C. 
Red alone.
(1) 
Vehicular traffic facing the signal shall stop before entering the nearest crosswalk at an intersection or at such other point as may be indicated by a clearly visible line and shall remain standing until green is shown alone, except that where warranted, the State of Illinois or the City on highways under their respective jurisdiction and control may permit vehicles to make a right turn under rules and regulations to be established by the State of Illinois or the City as the case may be.
(2) 
No pedestrian facing such signal shall enter the roadway unless he can do so safely and without interfering with any vehicular traffic.
D. 
Red with green arrow.
(1) 
Vehicular traffic facing such signal may cautiously enter the intersection only to make the movement indicated by such arrow but shall not interfere with other traffic or endanger pedestrians lawfully within a crosswalk.
(2) 
No pedestrian facing such signal shall enter the roadway unless he can do so safely and without interfering with any vehicular traffic.
E. 
In the event an official traffic control signal is erected and maintained at a place other than 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 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.
Whenever special pedestrian control signals exhibiting the words "Walk" or "Don't Walk" are in place, such signals shall indicate as follows.
A. 
Walk. Pedestrians facing such signal may proceed across the roadway in the direction of the signal and shall be given the right-of-way by the drivers of all vehicles.
B. 
Don't walk. No pedestrian shall start to cross the roadway in the direction of such signal, but any pedestrian who has partially completed his crossing on the walk signal shall proceed to a sidewalk while the "Don't Walk" signal is showing.
A. 
Whenever an illuminated flashing red or yellow signal is used in a traffic sign or signal, it shall require obedience by vehicular traffic as follows:
(1) 
Flashing red (stop signal). When a red lens is illuminated with rapid intermittent flashes, drivers of vehicles shall stop before entering the nearest crosswalk at an intersection or at a limit line when marked, or, if none, then before entering the intersection, and the right to proceed shall be subject to the rules applicable after making a stop at a stop sign.
(2) 
Flashing yellow (caution signal). When a yellow lens is illuminated with rapid intermittent flashes, drivers of vehicles may proceed through the intersection or past such signal only with caution.
B. 
This provision shall not apply at a railroad grade crossing. Conduct of drivers of vehicles approaching railroad grade crossings shall be governed by the rules as set forth in § 29-808 of this Ordinance.
A. 
No person shall place, maintain or display upon or in view of any highway any unauthorized sign, signal, marking or device which purports to be or is an imitation of or resembles an official traffic control device or railroad sign or signal or which attempts to direct the movement of traffic or which hides from view or interferes with the effectiveness of any official traffic control device or any railroad sign or signal.
B. 
This section shall not be deemed to prohibit the erection upon private property adjacent to highways of signs giving useful directional information and of a type that cannot be mistaken for official signs.
C. 
Every such prohibited sign, signal or other marking is hereby declared to be a public nuisance and the authority having jurisdiction over the highway is hereby empowered to remove the same or cause it to be removed without notice.
The City Traffic Engineer is hereby authorized:
A. 
To designate and maintain, by appropriate devices, marks or lines upon the surface of the roadway, crosswalks at intersections where there is particular danger to pedestrians crossing the roadway and at such other places as may be deemed necessary.
B. 
To establish safety zones for such kind and character and at such places as he may deem necessary for the protection of pedestrians.
A. 
The City Traffic Engineer is hereby authorized to mark traffic lanes upon the roadway of any street or highway where a regular alignment of traffic is necessary.
B. 
Where such traffic lanes have been marked, it shall be unlawful for the operator of any such vehicle to fail or refuse to keep such vehicle within the boundaries of any such lane except when lawfully passing another vehicle or preparatory to making a lawful turning movement.
All signs, signals, devices and marking installed or placed upon any street by direction of the Chief of Police or any officer of the State having authority to do so shall be taken and deemed to be notice to all persons using such streets of the regulations applicable thereto and failure to conform to such regulation shall be deemed to be a violation of this chapter.