Unintended Acceleration: Toyota's Black Boxes Don't Prove Driver Error.

Posted on October 1, 2010 by Kristine Meredith

Unintended or sudden acceleration problems have been around for years. From the beginning, car manufacturers have always wanted to blame the driver.  As long ago as the late 1980"s, manufacturers reported that "Startled and confused drivers hit the wrong pedal.” 

It’s no real surprise, then, that Toyota blames “driver error” for the recent spate of reported unintended acceleration cases involving its vehicles. It relies on preliminary findings from the National Highway Transportation Safety Administration that unintended acceleration cases may be due to what NHTSA calls “pedal misapplication”.

The problem with NHTSA’s findings are that they rely on data from a car's “EDR”, or event data recorder. An EDR is a device similar to the “black box” found on airplanes. But while the black box on an airplane is highly accurate, the EDRs installed in cars are not. They simply can’t be relied on, especially when it comes to unintended acceleration cases.

Here’s why relying on EDR data would give a false picture of what's behind cases of unintended acceleration:

  • Before 2007, EDRs did not capture pre-crash data. Since unintended acceleration is always a pre-crash event, the EDR is worthless for unintended acceleration cases in cars older than three years.
  • 95% of unintended acceleration cases are low speed events . Even the new EDRs, however, are not activated in low speed accidents.
  • In the rare high-speed unintended acceleration case, the entire power reserve in the air bag control module capacitor may be called upon to deploy the air bags, leaving none for the recorder and no data is stored.  Instead, the data is lost.
  • Unlike the aircraft Black Box data, EDR data has not been scientifically validated.

Toyota has admitted in other cases that the data from its EDRs are not reliable and should be kept out of court. If Toyota doesn’t trust the data from its own EDRs, why should we?
 

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Black Boxes in Cars

Posted on August 31, 2010 by Kristine Meredith

Event Data Recorders (EDRs) have been in cars since at least 1997. They are similar to the“black box” found on airplanes. The EDR in a vehicle is usually part of the vehicle restraint system and records information generally related to accidents. Some EDRs continuously record data and others are activated by crash-like events.

Manufacturers are not required to install EDR’s in the cars they manufacturer. But they do anyway. Ford, GM, Chrysler/Daimler and Toyota include them on most  models. 

In 2006, NHTSA set minimum standards for manufacturers who install EDRs.  The manufacturers must comply with those standards for EDR's installed on or after September 1, 2012. The NHTSA standards will require that the following data be recorded:  speed, engine throttle position, brake use, measured changes in forward velocity (Delta-V), driver safety belt use, airbag warning lamp status and airbag deployment times.

Currently, some manufacturers shroud the quantity and quality of EDR data in secrecy. For example, no one, other than Toyota, knows exactly what data Toyota’s EDRs record, what data is retrieved, and how it is processed and analyzed to produce a report.  Sean Kane of Safety Research and Strategies sheds some light on the murky subject of EDRs in his report found here.  All this will change in 2012, when NHTSA will require manufacturers to make their EDR data publicly available.

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