Seems to be much confusion here, maybe this will help!
This is how the SRS system is deployed;
Operational Sequence as follows: (1991 service manual)
(1) Bam! The cowl sensor activates, and one or both dash sensors activate.
(2) Electrical energy is supplied by the airbag inflator by the battery, or the backup power if the battery voltage is too low (Back up power unit and the cowl sensor are located inside the SRS control unit)
(3) Smack! Airbag deployment.
According to the maintenance manual at least the cowl and one dash sensor must be activated simultaneously for at least 0.002 seconds in order for the airbag to be deployed.
Indicated speed is not a factor in the operation of this system. If you hit something hard enough the cowl sensor will be waiting for input from the dash sensor and if you can set off a dash sensor you’re not going to be overly concerned about who’s at fault.
Not so sure about the 5 second thing, this is not a compliant EDR vehicle. However; the amount of information salvageable from the NSX SRS control unit and ECU after an accident is unknown. If the TCS control unit is removed from the car or the connection to the TCS control unit is disconnected all of the stored data in the memory is erased. Removing the clock fuse will reset the ECU. I don’t know enough about the SRS control unit to determine if it can in fact store information and or be cleared after power is removed ( remember this thing has enough juice to deploy the airbag if there's not enough power provided by the car). SRS fuse is located behind the driver’s side kick panel behind the hood release. Drew don’t stop, keep digging and I’ll keeping digging. Until we know for sure, we need to hammer down and find out if the NSX is equipped with anything that stores retrievable data about our personal use of our personal vehicles.
Relevant reading;
EDR/SDM/Black Box laws by state.
http://www.ncsl.org/programs/lis/privacy/blackbox05.htm
Since the 1970s, the federal National Highway Traffic Safety Administration (NHTSA) has been using the data from the EDRs to gather statistical data about car crashes.
NHTSA spokesman Ray Tyson estimates that 65 percent to 90 percent of all new vehicles have the boxes.
http://www.washingtonpost.com/wp-dyn/content/discussion/2006/02/16/DI2006021601781.html
Non-NSX (but if you own another vehicle, you should read it!)
Most new cars have an EDR integrated into the advanced airbag system, older cars may not. Locally here in Virginia there is a man on trial and his 1995 BMW is testifying against him. BMW black box is located in the transmission tunnel.
http://home.hamptonroads.com/stories/story.cfm?story=108755&ran=48188
If you own a GM product built after 1993 you are more than likely an owner of an EDR. If you own a Saturn, Hummer H2, Hummer H3, or a Saab 9-7X you’ve got an EDR installed. Love the new Cadillac XLR Roadster; it comes with an EDR/Black box. “Z06 owners are hosed!” The kink below is a listing of domestic cars that have an EDR that can be downloaded.
Lots of good info and links to get everyone started.
http://www.harristechnical.com/cdr.htm
I currently have two other cars I know have EDR’s installed. (I’m just happy about that).
Feel free to give me a hard time about anything I’ve written here. This is to benefit all!
Dwight