I came across an interesting article today. The article, "Is Big Brother in your car?" (via Thoughts of a Technocrat), informed me that cars have a "black box"... Not all cars, the manufacturers are listed in the article as: Ford, Mazda, Mitsubishi, Subaru, General Motors, Isuzu, and Suzuki. Harris Technical (a black box recovery company has a "complete" list of cars with black boxes (or EDR/CDRs). Apparently more than half of all new cars carry these devices, located in the cars underbelly, tied into the air bag system.
These "black boxes" (actually silver boxes) are being called a privacy concern by the ACLU. Both the police and your insurance company could have access to these devices to know all the details of how you were driving when an accident occurred.
I see this as a minor issue... I actually was more interested in learning that these devices existed... I decided to contact one of the companies that provide Crash Data Recovery, Harris Technical, and get answers to a few questions I had... I was impressed with how quickly Jim Harris replied to me. Below you will find the questions I posed to Jim as well as the excellent answers that he provided. Thanks Jim.
1. What details, exactly, are stored by the CDR?
The data stored by an EDR varies by year, make, model and sometimes by
options or sub-models (GT, XLS, etc). For pre-2000 GM vehicles, it is
mostly crash data. This is the velocity change of the vehicle through
the crash and does not include pre-impact data such as speed or brake
application. For post-2000 GM vehicles, through 2006, crash data plus up
to 5 seconds of pre-crash data including speed, brake application,
engine speed and throttle position may be stored. For some 2007 GM
vehicles, 2.5 seconds of pre-crash data is stored but much more
technical information regarding occupant restraints is also stored. For
most Fords, only crash data, however, in some models, Crown Vics for
one, up to 20 seconds of pre-crash data and crash data may be stored.
2. Do you have a sample of the output of the CDR that could be published?
On our web site, at
http://www.harristechnical.com/media.htm you can
find a pre-crash graph for a 2002 Saturn along with a photo of the
vehicle. A complete example report for a GM vehicle is attached in pdf
format. There are great variations between reports for different
vehicles but this is one that is currently common.
3. Is the data stored in any sort of encrypted/encoded format? Could
anyone, given the proper equipment, obtain data from any CDR?
Yes, the data is encoded in hex format. Translation of the hex values
requires software and hardware available from Vetronix, Corp. of Santa
Barbara, CA.
http://www.vetronix.com The equipment is available to
anyone that wants to buy it. This equipment does not support all
vehicles with EDRs as the vehicle manufacturers have not yet released
the required information. A list of currently supported vehilces is on
our web site at
http://www.harristechnical.com/downloads/cdrlist.pdf
Other vehicles may (do) have an EDR on board but data can only be
accessed, at this time, by the manufacturers, not the dealer technicians.
4. What sort of equipment is required to access a CDR? Is the
connection a standard data connection or proprietary? Could a
home-brew system be built?
The Vetronix CDR Tool is required at this time. While the Diagnostic
Link Connection, one method to obtain data from an EDR in certain
circumstances, is standard, direct connections to the EDR modules
requires proprietary cables. An interface box is provided in the CDR
Tool kit. CDR Tool software is also required.
5. Can this data be accessed on the fly? For example, could someone
with the proper equipment read the current data off the device, even
if it hasn't been written due to an impact. Could I drive a car into
your building and have you access any data off the CDR.
Crash data is recorded only in the event of a crash. Primarily this is
when there is an air bag deployment event or air bag deployment level
event. The deployment level event is when there is a crash that would
have ordered an air bag deployment but it was not for a variety of
reasons, driver out of position, etc. A non-deployment file may also be
written, such as hitting a pothole. This is a temporary file that will
either be erased after about 3 months or overwritten by an event of
greater magnitude. Without an event, there is no data stored.
6. Can the device be accessed without damaging a vehicle?
Yes. Unless access via the Diagnostic Link Connection does not work due
to damage to the vehicle's electrical system, then direct access must be
gained to the module. This usually involves cutting some carpet under a
seat or removing a center console.
7. Do you see any privacy concerns with the CDR?
The data recorded is not "private" information in the sense of SSN,
address, medical or financial records. However, it is private property.
A list of states with laws specific to accessing EDR data is available
at
http://www.harristechnical.com/cdr7.htm All 50 states also have
computer trespass laws that may apply to gaining access to EDRs. This
last item has not been tested in court to my knowledge.
8. Do these devices have a maximum lifetime? Will they operate the
full life of a vehicle, or are they useless after an accident? If they
are useless, can a replacement be purchased and installed?
EDRs are a component part of the air bag system. They are dependent
upon data from various sensors and other components operating correctly.
EDRs are expected to last the life of the vehicle.After an air bag deployment crash, the EDR, which is part of the air
bag control module, must be replaced to repair the air bag system. New
replacement modules are available through dealer parts departments. It
is recommended that only dealer technicians, with the proper training
and equipment, repair air bag systems. Buying a used one, even if the
seller "guarantees" it works, is a bad idea as you cannot tell if it is
going to function correctly when most needed.
Jim was also kind enough to include a Sample Report. I found all of this rather interesting... Is it a big invasion of privacy... not really, could it affect insurance claims definitely... Anyways... now you know as much as I do on the subject.
