Big Brother is in your car
When a traffic crash reconstructionist wanted to know the speed of a car in the seconds before it crashed into the side of a school bus, he found that information, and more, in the car's Event Data Recorder (EDR), a feature quickly becoming standard on all cars. The recorder, a four-inch square metal box, is currently installed in most recent GM vehicles and select 2000 and later Ford vehicles.
List of all vehicles with an EDR on board.
Originally designed to improve air bag performance based on the severity of the collision, the event data recorder can tell traffic accident investigators about the car's speed, engine RPMs, how far the accelerator pedal was pressed, if the brakes were applied, whether the driverís seatbelt was buckled and what warning lights were on - all from about five seconds before impact.