President’s Message: CDR User’s Summit

Jan 31, 2013 by

The annual CDR User’s Summit was held this January in Houston, with approximately 200 attendees.  I had the privilege of attending again this year and was both trained and educated on the latest updates in this rapidly advancing technology.  We heard from representatives of Bosch, several Original Equipment Manufacturers (OEMs), and SAE, as well as specific companies deeply involved in CDR training.  Current estimates of CDR coverage say that there are 264 million cars on the road in US/Canada.  Of those, 70M are GM products of which 75% have CDR coverage.  Ford has 49M vehicles of which 39% are covered.  Toyota has 61% coverage and Chrysler has 26% coverage.

For you readers who are not familiar with CDR technology, let me give you a brief overview.  Roughly three decades ago, automakers looked at the trend of increasing annual motor vehicle deaths, and sought a way to slow or even reverse the trend.  They already had added safety glass, seatbelts, and padded dashboards, but they needed something more.  So they came up with airbags.

Now if you were the CEO of GM in those early days, and a group of engineers told you that they wanted to install an explosive device 18 inches from the face of every one of your customers, wouldn’t you be at least a little skeptical?  How do you know when to set it off or when not to?  How do you keep from killing people with your “safety device”?  The answer was the Airbag Control Module (ACM).  This was basically a small computer that read sensor inputs, made calculations, and then, when appropriate, commanded the airbags to deploy, thus potentially saving the customer’s life.  The calculations had to be quick, and the decisions had to be right.

The engineers carefully monitored many test crashes with deployed airbags to verify that their product was performing as they had designed.  An integral component of the ACM is the Event Data Recorder (EDR), which captures specific parameters from a deployment event and saves them for later transfer to a computer for analysis.  The transfer or imaging process uses a Crash Data Retrieval (CDR) tool.  This tool was made by a company called Vetronix, which was the only company GM used for this function.  This data retrieval became part of the quality control process to verify proper functionality.

While GM was the leader, it didn’t take long for Ford and others to also adopt airbag technology.  It also didn’t take long for them to form the same exclusive Vetronix relationships.  Fast forward a few more years and the multinational giant Bosch bought Vetronix and rebranded the equipment with the Bosch name.  As a sidelight, Bosch was also one of leading manufacturers of airbag control modules, so they were no strangers to the game.

CDR kit

Along the way the government also got involved, as they too are interested in crash safety.  The National Highway Traffic Safety Administration (NHTSA) ruled that if a manufacturer installs an airbag that stores crash data, then it must be commercially downloadable (such as using Bosch equipment and not just dealer equipment), and that data must conform to specific standards.  This was codified in 49 CFR 563.  Their initial implementation date of 2010 was extended to September of last year when some of the OEMs couldn’t meet the original deadline.  There are 15 specific data elements that must be captured, along with specifications for precision and accuracy.  Recent legislation has removed the voluntary aspect; now all OEMs must provide EDR download capability by September of 2014 for cars with GVWR under 8,500 lbs.

The current list of covered models that can be downloaded by the Bosch tool includes Toyota, Nissan, Ford, GM, Chrysler, Mazda, Fiat, BMW, Volvo, Suzuki, and Honda vehicles.  Generally, each time an OEM signed up with Bosch, they covered models from then forward, but occasionally they also provided coverage of earlier models.

With more than a dozen conference speakers, there was a lot of material at the conference, most of it fairly technical.  One presentation that may be of interest to you, however, was on the topic of “reprogramming” or “clearing” ACMs.  An ACM can capture a limited number of events (anywhere from two to five depending on the OEM).  When it is full of locked events, it must be replaced, just as the deployed airbags must be replaced.  Of course, they are expensive.  This has created a cottage industry of Internet companies that advertise that they can reprogram an ACM (for $49 to $125), and therefore you can reuse instead of replace.

One conference speaker put them to the test.  He obtained several modules that were involved in deployment events.  Then he downloaded them and saved the event files.  He also carefully photo-documented them with the goal of being able to detect any physical changes that might occur.  He shipped them off to three different online companies, paid the fees, waited a couple weeks, and received them back.  He then re-downloaded them and compared the reports.  The results were less than satisfactory.  In three out of four cases, some residual (or incomplete) crash data remained in the EDR.  Some ACMs had been opened, as evidenced by the tampered screws and seals.  Some had holes drilled in the cases, presumably to allow access to the electronics directly underneath the holes.

Two major issues are created by the presence of reprogrammed ACMs out on the road.  First, will they store fresh data?  If an ACM is reprogrammed and then downloaded by the Bosch tool, is the data that the analyst is looking at from the current crash, or maybe from an event that happened months earlier, or is it a combination of the two?  Secondly, in a crash, an ACM may experience several events that would cause it to deploy an airbag (a glancing blow, pole strike, bridge embankment).  But when the airbag deploys, it sets a flag to record that fact and the second or third events have no pyrotechnic reaction.  If a reprogrammed ACM still has that deployment flag set, then it won’t know that there is a new airbag ready for use.  In a crash, the sensors will report the need, the ACM will calculate and decide, but the already deployed flag will prevent the firing of the replacement airbags.



As analysts, we need to be wary of reprogrammed ACMs.  As drivers we need to be assured that a reprogrammed ACM will deploy the airbags when needed.  Unfortunately, there is no evidence yet that they will or won’t.


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