NEW YORK (CNNMoney.com) -- The National Highway Traffic Safety Administration is launching an investigation into whether Toyota Motor Co. delayed telling investigators in 2005 that a known defect on compact trucks in Japan was also a problem in the United States.
Toyota (TM) later recalled the trucks in the U.S. for a steering relay rod that was prone to cracking.
The automaker had recalled trucks in Japan for the problem in 2004, according to the current probe. As required by law, the company reported the action to NHTSA. But in that notice, according to the agency, Toyota informed NHTSA that it had received no complaints of the problem in the U.S. and that differences between trucks sold in Japan and the U.S. -- as well as different operating conditions -- meant the issue wasn't a problem here.
On Friday afternoon, NHTSA received internal Toyota documents unearthed through a private lawsuit, a NHTSA official said, that showed Toyota actually had received complaints about the same problem with some trucks and SUVs in the U.S. -- complaints that the automaker allegedly had not shared with NHTSA.
In 2005 Toyota recalled some compact trucks and 4Runner SUVs in the U.S. for the same problem.
"Safety is our number one priority and we take our responsibility to protect U.S. consumers seriously," Transportation Secretary Ray LaHood said in a statement. "With new assurances from Toyota about their efforts to improve safety, I hope for their cooperation in getting to the bottom of what happened."
LaHood had met with Toyota chief executive Akio Toyoda earlier Monday in Japan.
"Toyota has received an Information Request from NHTSA in regard to this issue," Toyota spokesman Brian Lyons said in an email. "We will cooperate with the agency's investigation."
Under federal regulations, automakers are required to inform the agency within five days of determining that a safety defect exists in one of its products. Failure to abide by reporting rules carries a maximum fine of $16.4 million.
Toyota recently paid one such fine for allegedly failing to report problems with gas pedals in some of its cars in a timely manner. Although Toyota agreed to pay the fine in that case, the automaker did not admit any wrongdoing.
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