Updated at 2:34 p.m. EST
Transportation Secretary Ray LaHood said Tuesday his agency may recommend that every new vehicle sold in the U.S. be equipped with brakes that can override the gas pedal. The idea seemed to be gaining support among lawmakers as Toyota officials returned for a third congressional hearing on lethal safety defects.
"We will not rest until these cars are safe," LaHood told the Senate Commerce Committee.
His testimony came as federal safety officials the number of reported deaths linked to sudden acceleration in Toyota vehicles, through the end of last month. Previously, 34 deaths were blamed on the problem.
"I think you'll see some changes in the way they do business," LaHood told the panel.
Toyota Motor Corp. and federal regulators both faced renewed questions Tuesday from Congress over the giant Japanese car company's troubled safety record.
"We know something has gone terribly wrong," said committee chairman Jay Rockefeller, a Democrat. "The system meant to safeguard against faulty vehicles has failed, and it needs to be fixed and it needs to be fixed right away."
Multiple recalls have damaged Toyota's reputation and set the stage for large numbers of death and injury lawsuits amid a criminal investigation by federal prosecutors in New York, a probe by the Securities and Exchange Commission and more scrutiny from the Transportation Department. Since September, Toyota has recalled about 6 million vehicles in the U.S.
There was further evidence Tuesday of how the broad recalls and safety questions have affected Toyota's business. The company's U.S. sales fell 9 percent in February while rivals General Motors and Ford .
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Sen. Barabara Boxer, D-Calif., and Sen. Byron Dorgan, D-N.D., pressed Transportation Secretary Ray LaHood on whether the National Highway Traffic Safety Administration's previous investigations into Toyota safety complaints were compromised by conflicts of interest.
Both cited a by CBS News investigative correspondent Sharyl Attkisson, which found that Christopher Santucci, a former NHTSA employee who conducted defects investigation into automakers, used his contacts at Toyota to negotiate his employment with them in 2003.
At Toyota, he worked under fellow ex-NHTSA official Christopher Tinto. Records show the two worked to limit safety probes into reports of Toyotas surging out of control.
LaHood said the department investigated the two and that they didn't appear to be engaged in illegal activity.
One element of new legislation could be a requirement that all newly manufactured cars sold in the United States have an override system.
Toyota has said it will put such a system into all future vehicles and will retrofit many recalled models. More than 8 million Toyota cars have been recalled in all because of sudden acceleration or braking defects.
Meanwhile, Toyota's North American president, Yoshimi Inaba, said Toyota was setting up an outside panel to advise the company's North American affiliates on quality and safety issues. He said Rodney Slater, a U.S. transportation secretary during the Clinton administration, would lead the group.
The panel will have direct access to company president Akio Toyoda and will make sure the company's new safety and quality controls "conform to best industry practices," Inaba said in prepared testimony to the committee.
The backup safety system under discussion would override the accelerator if the gas and brake pedals were pressed at the same time.
"Why don't we require every manufacturer to do this?" Rockefeller asked.
LaHood responded: "We are looking at the possibility of recommending the brake override system in all newly manufactured automobiles."
The new number of 52 deaths was surfaced by the National Highway Traffic Safety Administration, part of the Department of Transportation. Federal officials haven't formally confirmed the links between deaths and Toyota defects but have received a spike in complaints since Toyota began a series of big recalls in October.
Sen. Daniel Inouye, a Democrat, noted that not just Toyota cars have defects, but that other automakers also have been subject to millions of recalls. "It is not a Toyota problem, it is an industry problem," he said.
Inouye noted that over much of the past decade, recalls of vehicles made by Ford, General Motors and Chrysler dwarfed Toyota recalls.
"If it is an industry problem, we should hear from the industry, instead of just Toyota," Inouye said.
Several senators on the Committee have , including Rockefeller, who helped land a Toyota engine plant in Buffalo, W.Va., during the 1990s.
Rockefeller said, "It is clear that somewhere along the way public safety took a back seat and corporate profits drove the company's decisions."
Rockefeller last month asked the Transportation Department's Inspector General to conduct an audit of the government's response to the recalls and has sought information from Toyota, the government and auto insurers.
The Senate panel - formally the Senate Committee on Commerce, Science and Transportation - is probing whether Toyota and federal safety regulators acted swiftly enough.
Toyota President Akio Toyoda before the House Oversight Committee to be more responsive to driver complaints and safety warnings from the government. Toyoda made a similar promise to improve quality control while apologizing Monday to Chinese Toyota owners.
But the company still faces lingering doubts over the cause of the problems, which it has blamed on gas pedals that can get obstructed by floor mats or stick due to design flaws. Safety experts have said the electronic systems of Toyota vehicles also could be to blame. Toyota insists there is no evidence of an electrical cause.
Rockefeller said that federal investigators were reluctant to investigate whether vehicle electronics were to blame for problems with cars speeding out of control because it is harder to detect electronic problems.
NHTSA "would rather focus on floor mats than microchips because they understand floor mats," Rockefeller said.
LaHood responded that his agency will do a "complete review" of the electronics issue.
Adding to Toyota's woes, the automaker said Tuesday it is repairing more than 1.6 million vehicles around the world, including the U.S. and Japan, for .
NHTSA is seeking records on Toyota's recalls and investigating whether electronics were behind the vehicle defects. NHTSA also continues to look into steering complaints from drivers of the popular Corolla model.
Joining LaHood at the witness table was NHTSA Administrator David Strickland, a former Senate Commerce Committee aide. The Senate committee also heard from Clarence Ditlow, president of the Center for Auto Safety, which has investigated the Toyota complaints.
Questions remain over whether the recalls have fully addressed the problem. A review conducted by The New York Times found numerous complaints to the government about speed control problems in Toyota Camry sedans not included in the recalls.
The 2002 Camry, for example, was not part of the recall but had about 175 speed control complaints, with about half involving crashes, the Times reported on its Web site Monday night. The 2007 Camry, meanwhile, which was included in the recall, had 200 speed control complaints, with fewer than one-quarter resulting in accidents. The Times analyzed 12,700 complaint records filed in the United States during the past decade.
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