Method and apparatus for activating a crash countermeasure using a transponder and adaptive cruise control

1. Technical Field A method for operating a pre-crash sensing system for a first vehicle () proximate a second vehicle (). The second vehicle () generates a cruise control signal. The cruise control signal is detected at the first vehicle. In response to the cruise control signal a vehicle data signal from the first vehicle is generated. The first vehicle data signal may include various information from the first vehicle including sensor data, heading data, and vehicle classification data. The transponder of the first vehicle may also be activated in response to an urgent event. The data signal is formed in response to the urgent event and broadcast from the first vehicle to all nearby vehicles.