The driver of a motor vehicle shall when reasonably necessary to ensure safe operation give audible warning with his or her horn, but shall not otherwise use such horn when upon a highway. For purposes hereof, the word "highway" shall mean the entire width between the boundary lines of every way publicly maintained when any part thereof is open to the use of the public for purposes of vehicular traffic or located on public school property. (Ord. 3157, 12-15-2003)