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Black Box

5.2K views 14 replies 12 participants last post by  john_w  
#1 ·
Just wondering.. is there a 'Black Box' recorder installed, and would that affect potential insurance claims if you happen to 'break the Jeep'. Just wondering if insurance claim could be denied if 'vehicle not used as intended..'
 
#3 ·
bperrypa said:
Just wondering.. is there a 'Black Box' recorder installed, and would that affect potential insurance claims if you happen to 'break the Jeep'. Just wondering if insurance claim could be denied if 'vehicle not used as intended..'
yes the black box is on the jk.read your owners manual and it tells you that their may use the info.
 
#7 ·
bperrypa said:
Just wondering if insurance claim could be denied if 'vehicle not used as intended..'
It's a Jeep Wrangler, advertised by the manufacturer as being the most capable off-road machine in production. They even debuted the thing to automotive journalists in the African jungle! Of course, if you drive through a puddle and get in an accident, you bet the insurance company will claim that it wasn't being used as intended... :rofl:
 
#9 ·
Almost every car built today have event data recorders. The vehicle bus is constantly transmitting data like speed, brake pedal status, accelerator position, etc. The airbag controller will take a snapshot of this data and store it if airbags are deployed.

The event data recorder is simply some flash memory located in the airbag ECU and cannot be disabled.
 
#11 ·
Saw a TV documentary about these data recorders. It takes a "snapshot" of the vehicles speed, engine RPM, braking data, seatbelts, etc for the previous 5 seconds if the airbags are deployed. This show had actual cases of people serving prison time for accidents where it was determined they were criminally negligent based solely on the information in this little "black box".
They showed pictures of the data recorder with the warning that if the box were disconnected, the airbags would not work. The box they showed looks exactly like the small metal box located on the hump in front of the console and under the dash on my '03 TJ.
I wondered what that was the last time I put my carpet back in. Now that I know, I'm shocked to say the least!:eek:
 
#12 ·
The "black box" is actually the airbag electronic control unit (ECU). You have to have it on all the time if you want airbag protection, because the job of this module is to read in acceleration sensor data and decide if you are going to roll over or get into a crash. If that is the case, this same module is the one that sends the firing current to the squibs that actually deploy the airbags. When the crash event occurs, that is the time that the "black box" function kicks in and it writes the data to flash memory located inside the ECU - which is that box you see typically in the center tunnel area of most vehicles. The reason it is near the center of the car is so it gets the most accurate yaw rate (for rollovers) and acceleration data in addition to the external sensors.

Here's another word of warning: Don't ever try to unbolt the module while it is connected and powered up. You can fire your airbags just by turning the module over if the unit is on! Service manuals and warnings on the unit all warn of this, but you know how we all like to read :D
 
#13 ·
mcbuck said:
Saw a TV documentary about these data recorders. It takes a "snapshot" of the vehicles speed, engine RPM, braking data, seatbelts, etc for the previous 5 seconds if the airbags are deployed. This show had actual cases of people serving prison time for accidents where it was determined they were criminally negligent based solely on the information in this little "black box".
They showed pictures of the data recorder with the warning that if the box were disconnected, the airbags would not work. The box they showed looks exactly like the small metal box located on the hump in front of the console and under the dash on my '03 TJ.
I wondered what that was the last time I put my carpet back in. Now that I know, I'm shocked to say the least!:eek:
I saw that, too, and was wondering how it oculd record the 5 seconds previous to the deployment of the airbags? I don't doubt the accuracy of teh story, by how does it know that the airbags are going to deploy?
 
#14 ·
john_w said:
Almost every car built today have event data recorders. The vehicle bus is constantly transmitting data like speed, brake pedal status, accelerator position, etc. The airbag controller will take a snapshot of this data and store it if airbags are deployed.

The event data recorder is simply some flash memory located in the airbag ECU and cannot be disabled.
The story I saw (see above note) said that not all had them and to look for something specific in the owner's manual. I cannot remember what it was, but I looked in my Jeep's manual and it didn't have it.

In a June 2004 announcement, the NHTSA proposed requiring manufacturers to include information about black boxes in owners' manuals for cars equipped with the technology. Although the federal traffic agency continues to gather feedback on its latest set of black-box recommendations, it's too early to say how the input will shape the agency's final ruling, a representative said. For now, the NHTSA has left it up to the courts to decide whether to admit the data as evidence.
This is a quote from cnet.
 
#15 ·
sardog12 said:
I saw that, too, and was wondering how it oculd record the 5 seconds previous to the deployment of the airbags? I don't doubt the accuracy of teh story, by how does it know that the airbags are going to deploy?
The module doesn't know you are going to crash 5 seconds ahead of time... but the data is "streaming" on the vehicle bus (an internet if you will inside your car) at all times. So think about a TIVO and how it can do an instant replay. There is a small buffer of memory in the airbag ECU that is constantly recording the bus traffic; but only 5 seconds worth. It's constantly overwriting this in the RAM memory. This is kind of how TIVO works with their instant replay...

So when the time arrives and the ECU says "I'm firing airbags now", the ECU will then take that 5 seconds of most recent history and write that as a record into non-volatile flash memory. Now you have a record that can be read out at a later time that shows what happened in the very short time leading up to the deployment event.

And yes, these records do get used in court.