Whenever an illuminated flashing red or yellow signal is used in conjunction with an official traffic-control device, it shall require obedience by vehicular traffic as follows:
1. When a red lens is illuminated with rapid intermittent flashes, drivers of vehicles shall stop before entering the nearest crosswalk in 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 required stop.
2. When a yellow lens is illuminated with rapid intermittent flashes, drivers of vehicles may proceed past such signal and through the intersection or other hazardous location only with caution.