Re: "Black Box" information retention?

Oct 09, 2007 14 Replies


>> obd0 = zero


>>> obd1 = 30 secs
> Having typed the above, I remember now that I read once (not online) that
> the black box actually holds more like a minute to five minutes of engine-
> running time.
>
> The automakers are interested only in the events immediately prior to,
> and during, a collision or mechanical failure.\

Well again, the question comes forth...how far back is the information about a crash retrievable?


If I wanted to access crash information from a day in the summer...would it still be there?


Does it hold that information indefinitely...until the next crash? ...until you drive it again? ??


Thanks for your help!


------------------------------

Yes, the info would still be there if the vehicle has not been powered up since the crash. There would be x minutes of data available.

You said the car has been driven since. If the 'black box' is in the car, the data is now gone.

'Curly'

"Rob" wrote in news:9qWdnekUaOK8WpbanZ2dnUVZ snipped-for-privacy@comcast.com:

From what I understand and have read, the information is very short-lived. If you've driven the car more than a few minutes since the summer, summer's information is long gone.

I have asked these questions of somebody I know who is in the trade. If I get a response, I will post the results here.

reminds me of the joke about Bubba.

the black box was set up to record voices just before a collision.

From what I understand and have read, the information is very short-lived. If you've driven the car more than a few minutes since the summer, summer's information is long gone.

I have asked these questions of somebody I know who is in the trade. If I get a response, I will post the results here.

motsco_ wrote in news: snipped-for-privacy@corp.supernews.com:

I've got some answers:

1) The info is stored by the SRS computer, not the engine's ECU.

2) The SRS computer stores a "snapshot" of the final state of all the inputs when the engine was stopped for the last time.

3) The SRS computer also stores about 15 seconds of real-time data immediately prior to the last engine stoppage.

4) Dealership employees and techs are not able to access the info stored. This is only accessible by Honda.

I have just asked when they started storing this info.

If by "black box" you are referring to the SRS (supplemental restraint system) Unit.

The answer is YES. Yes the SRS unit does store limited data, but only at the time of a deployment event.

Dealers can only access DTCs with their scan tool, and nothing else (as related to deployment events.)

Any Honda/Acura SRS Unit that can store DTCs, can and will store "deployment" DTC(s) at the time of deployment. This event data only records at the time, of a deployment.

The SRS Unit does not know the date, time, or speed of the vehicle, at the time of deployment. What it does know and record, in permanent memory, is which seat belt was buckled, vehicle deceleration rate (in ms), which airbags, buckles or belt tensioners deployed.

Cars with OPDS, SWS or ODS might also record front passenger weight (SWS/ODS), and front passenger position (OPDS/ODS), at the time of the deployment.

So, in conclusion, no deployment, no data stored.

-- Tp,

-------- __o

----- -\

further reading:

formatting link
now imagine your onstar "driver assistance" system phoning home your, er, "driving habits" to your insurance company, complete with gps coordinates in real time....

also:

formatting link

---------------------------

Slightly OT, but I've heard of rental agencies handing the customer a big 'surcharge' for breaking the TERMS & CONDITIONS of the rental agreement for driving the vehicle like it was stolen. (the GPS tracking flagged them). They apparently thought they could bet from 'A' to 'B' at the speed of a rented jet. :-)

'Curly'

well, you /could/ do this with an individual's cell phone too. or credit card as you buy fuel along the freeway. or use license plate reading cameras every few miles. or have a transponder in every license plate and sensors in the road. in fact, there are already sensors in the road in many places. you know where there are two rings in the lane one after the other? those are used to sense average vehicle speeds and density, and thus manage traffic flow. putting a transponder in the license plate and having it talk to one of those speed sensors as you drive over it is trivial. automatic ticket issuance is more trivial still.

jim beam wrote in news:OZSdnf-ny-BJd43anZ2dnUVZ snipped-for-privacy@speakeasy.net:

I often wonder if those double sensor loops are used to change an upcoming light to red if you're exceeeding the speed limit. It's possible. And all they need is to add a camera to get your lic.plate number as you trip the sensors at SL+ xMPH.Then you get a ticket in the mail. No need for any transponders in your car.(or the transponder microchip could be in the plate itself,in the sticker,or a reflective barcode read by a laser scanner.)

I don't know that they can do that; however there is a setup near my house where they do a radar gun to do exactly that. I'm not sure *why,* either - the light is at the bottom of a steep grade on a road signed at

30 MPH, but there is no intersection within 1/4 mile or more in either direction. I'm not sure at what speed the light will turn red, but a speeding vehicle is the only thing that will trigger the light.

nate

Nate Nagel wrote in news: snipped-for-privacy@news2.newsguy.com:

more than 30 years ago,in Buffalo,on Delaware Ave going through Delaware Park,there was a speed-controlled traffic light.Exceed the 30MPH speed before the light and the light would turn red before you got past it(unless you were REALLY going fast!),and the light had no crossing road.No radar was used. It was placed halfway thru Delaware Park.I don't know if it is still that way,haven't been back there in many years. That is the only one I have ever encountered.Although I'm beginning to suspect one light in an Orlando suburb,near me.

There is currently no light on Delaware Ave in the S curves (the area passing through the park). There is one just before the curves (at an intersection) and one just after (again, an intersection).

Must have been removed quite a while ago, as I don't remember it. The Delaware S-Curves are a fun place to test your vehicle (at night, when traffic is very light)...

Combined speed and rlc cameras already exist.

Joe wrote in news:ePWdnbPbJLqWxozanZ2dnUVZ snipped-for-privacy@giganews.com:

yes,the old light was in the middle of the S curves,to slow traffic down. As I said,around 30 years ago. They probably removed it once they found that people were able to beat it.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required