(a) The driver of a vehicle approaching a yield sign shall, in obedience to such sign, slow down to a speed reasonable for the existing conditions, or shall stop if necessary, and shall yield the right of way to any pedestrian legally crossing the roadway on which he is driving, and to any vehicle in the intersection or approaching on another highway so closely as to constitute an immediate hazard. Such driver having so yielded may proceed, and the drivers of all other vehicles approaching the intersection shall yield to the vehicle so proceeding, provided, that a driver who enters a yield intersection without stopping and has or causes a collision with a pedestrian in a crosswalk or a vehicle in the intersection shall prima facie be considered not to have yielded as required herein. The foregoing shall not relieve the drivers of other vehicles approaching the intersection at such distance as not to constitute an immediate hazard from the duty to drive with due care to avoid a collision.
(b) The driver of a vehicle approaching a yield sign, if required for safety to stop, shall stop before entering the crosswalk on the near side of the intersection or, in the event there is no crosswalk but a stop line is marked, the vehicle shall be stopped on the near side of such stop line. If neither a crosswalk nor stop line is marked, then the vehicle shall stop at the point nearest the intersecting roadway where the driver has a view of approaching traffic on the intersecting roadway. (1974 Code Sec. 3-67)