February 10, 2011
by Fleet Management staff
At the end of a 10-month study in the US, NASA engineers found no electronic flaws that could be responsible for producing the unintended acceleration problems that prompted so many Toyota recalls last year.
The two mechanical safety defects identified by The National Highway Traffic Safety Administration (NHTSA) more than a year ago–“sticking” accelerator pedals and a design flaw that enabled accelerator pedals to become trapped by floor mats–remain the only known causes for these kinds of unsafe unintended acceleration incidents. Toyota has recalled nearly eight million vehicles in the US alone for these two defects.
The US Department of Transportation released results from an unprecedented ten-month study of potential electronic causes of unintended acceleration in Toyota vehicles. The NHTSA launched the study last spring at the request of Congress, and enlisted NASA engineers with expertise in areas such as computer controlled electronic systems, electromagnetic interference and software integrity to conduct new research into whether electronic systems or electromagnetic interference played a role in incidents of unintended acceleration.
US transportation secretary Ray LaHood said, “We enlisted the best and brightest engineers to study Toyota’s electronics systems, and the verdict is in. There is no electronic-based cause for unintended high-speed acceleration in Toyotas.”
Steve St. Angelo, Toyota’s chief quality officer for North America, responded to the report:
“Toyota welcomes the findings of NASA and NHTSA regarding our Electronic Throttle Control System with intelligence (ETCS-i) and we appreciate the thoroughness of their review. We believe this rigorous scientific analysis by some of America’s foremost engineers should further reinforce confidence in the safety of Toyota and Lexus vehicles. We hope this important study will help put to rest unsupported speculation about Toyota’s ETCS-i, which is well-designed and well-tested to ensure that a real world, un-commanded acceleration of the vehicle cannot occur.”
In conducting their report, NASA engineers evaluated the electronic circuitry in Toyota vehicles and analyzed more than 280,000 lines of software code for any potential flaws that could initiate an unintended acceleration incident. At the Goddard Space Flight Center in Maryland, NASA hardware and systems engineers rigorously examined and tested mechanical components of Toyota vehicles that could result in an unwanted throttle opening.
At a special facility in Michigan, NHTSA and NASA engineers bombarded vehicles with electromagnetic radiation to study whether such radiation could cause malfunctions resulting in unintended acceleration. NHTSA engineers and researchers also tested Toyota vehicles at NHTSA’s Vehicle Research and Test Center in East Liberty, Ohio to determine whether there were any additional mechanical causes for unintended acceleration and whether any of the test scenarios developed during the NHTSA-NASA investigation could actually occur in real-world conditions.
“NASA found no evidence that a malfunction in electronics caused large unintended accelerations,” said Michael Kirsch, principal engineer at the NASA Engineering and Safety Center (NESC).
To read the executive summary and findings of the NASA report, click here.