NASA, the US space agency, and the National Highway Traffic Safety Administration said a 10-month probe of defects that led to recalls of more than eight million vehicles worldwide found no electronic causes.
Safety advocates and some lawmakers had pointed to electrical faults as a reason for the reports about Toyota.
The US report, released in Washington and cited in a Bloomberg report, found no causes for the unintended acceleration incidents other than sticking accelerator pedals and floor mats that jammed the pedals down. Those were the causes Toyota, based in Toyota City, Japan, had identified.
“We feel that Toyota vehicles are safe to drive,” US Transportation Secretary Ray LaHood said in Washington.
LaHood, who in February 2010 said Toyota owners should stop driving their cars, said he later advised his daughter to buy a 2011 Toyota Sienna, which she did.
The study should “further reinforce confidence in the safety of Toyota and Lexus vehicles,” Steve St. Angelo, Toyota’s chief quality officer for North America, said in a statement.
St. Angelo said Toyota would continue to co-operate with NHTSA and outside experts.
The review may ease questions about quality at Toyota because the company recalled the vehicles to fix the accelerator pedal issues.
Almost half of the reports about unintended acceleration in Toyotas were sent to NHTSA in February and March 2010, when congressional hearings were held, NHTSA Deputy Administrator Ron Medford said in the Bloomberg report.
“We received the majority of those reports after Toyota began its recalls,” Medford said.
The “vast majority” of complaints about Toyotas were at low speeds or when the vehicle was stationary, the official added.
“What most likely happened was pedal misapplication,” he said. “The driver stepped on the gas rather than the brake or in addition to the brake.”
NASA studied whether electromagnetic interference may have caused unintended acceleration.
NASA investigators used Chrysler Group LLC’s test facility in Auburn Hills, Michigan, for its vehicle testing work, and bombarded vehicles with electromagnetic radiation, the Transportation Department said.
Mechanical components were tested at NASA’s Goddard Space Flight Center in Maryland.
