Toyota Motor Corp on Monday sought to discredit an outside study critical of its electronic safety systems and said it had found no flaw with its throttle controls.
The conclusions, which were announced at a news conference, marked an attempt by the automaker to reassure consumers it has safety issues under control as it works to win back sales seven weeks into a recall crisis that has tarnished its reputation.
Toyota called the event to discredit what it said were mistaken conclusions being drawn from a study of its accelerator controls by David Gilbert, an auto engineering expert at Southern Illinois University.
Toyota has recalled over 8 million vehicles worldwide for mechanical problems with its accelerator assembly that can cause sticking and for the risk that floormats could trap an accelerator.
Unintended acceleration in Toyota and Lexus vehicles has been linked to at least five U.S. crash deaths since 2007. Authorities are investigating 47 other crash deaths over the past decade.
The U.S. National Highway Traffic Safety Administration has also said it is looking into more recent complaints from drivers who say they suffered acceleration problems even after their vehicles were fixed in the recent recall effort.
Those complaints have been seen by some as further evidence that Toyota could face a problem with vehicle electronics or software that could go beyond the mechanical fixes it has announced under its recalls.
But Toyota spokesman Mike Michels said the automaker had found that post-recall accelerator complaints appeared to reflect a small number of cases where repairs at dealerships had not been performed correctly.
We're confident in our electronic throttle control systems, Michels said.
TOYOTA: NO REAL-WORLD EVIDENCE OF FLAW
Gilbert told a congressional panel in late February that he had found a way to simulate a flaw in Toyota's accelerator controls so that the vehicle could surge forward without a fault code being generated for an onboard computer Toyota has designed as a safeguard.
But Toyota said an outside review of Gilbert's findings by a Stanford University expert and by the engineering consulting company Exponent had not found evidence that conditions described by Gilbert could occur in real-world driving.
Chris Gerdes, a professor of mechanical engineering at Stanford and director of the university's Center for Automotive Research, said Gilbert had essentially rewired Toyota's accelerator system to generate his results, which became the subject of a widely discussed ABC News report that aired last month.
Fundamentally, you cannot rewire a circuit and expect it to behave as designed, Gerdes told reporters.
Exponent principal engineer Subodh Medhekar said the company was able to cause a range of rival vehicles to accelerate by manipulating throttle controls in the way Gilbert had described. As engineers we could rewire anything, but that is not realistic, Medhekar said.
Kristen Tabar, who manages electronic systems engineering for Toyota's North American operations, also said that the automaker had not found any evidence of corrosion or other flaws with its wiring systems that would suggest that the conditions described by Gilbert had occurred in its vehicles.
Toyota is facing dozens of lawsuits stemming from its recalls and both sides in that litigation have been working to line up expert witnesses.
Gilbert, who could not be reached for comment on Monday, has received some funding from the Safety Research and Strategies, a safety advocacy that has in turn taken funding from trial lawyers with cases pending against Toyota.
For its part, Toyota has hired Exponent and has provided financial assistance to Stanford's auto safety center.
Toyota and Exponent said they were continuing to test other explanations for unintended acceleration that would go beyond the problems it has identified.
(Reporting by Kevin Krolicki and Bernie Woodall; editing by Carol Bishopric)