An emergency vehicle transmits a Vehicle Present Signal when in transit on public roads responding to an emergency. The signal can include information relating to the type of emergency vehicle, local highway and terrain data, and the location, speed and direction of travel of the emergency vehicle. When the Vehicle Present Signal is detected by a first vehicle, a functional circuit within the first vehicle calculates the distance between the emergency vehicle and the first vehicle. If the vehicles are within a predetermined distance, a warning signal activates one or more warning systems, thereby notifying the driver of the first vehicle that an emergency vehicle is in the vicinity. A dead-band defined by first and second predetermined distances can be incorporated to prevent rapid cycling of the warning signal.