WASHINGTON-U.S. regulators stepped up their investigation of Toyota Motor Corp. on Tuesday, demanding documents from the Japanese auto maker to determine if it conducted recent recalls "in a timely manner."
The National Highway Traffic Safety Administration said it was using its statutory authority to compel Toyota to provide paperwork showing when and how the company learned of defects that led to the recall of six million vehicles in the U.S.
Federal law requires that car makers notify NHTSA within five days of spotting a safety defect and then promptly conduct a recall, the agency said.
The probe could lead to a maximum civil fine of up to $16.4 million if Toyota is found to have violated statutory obligations. No auto maker has been fined more than $1 million for such a violation.
"Our top priority is safety and we expect that all manufacturers address automotive safety issues quickly and in a forthright manner," said David Strickland, NHTSA's administrator.
Toyota said in a statement it was cooperating with regulators and planned "to provide all the information they have requested."
"Toyota takes its responsibility to advance vehicle safety seriously and to alert government officials of any safety issue in a timely manner," the company said.
Toyota has 30 to 60 days, depending on specific requests, to provide the documents, NHTSA said.
The increasing pressure by NHTSA on Toyota comes a week before the U.S. Congress holds hearings on the car maker's safety troubles. Some lawmakers have questioned NHTSA's response to the problems, and the agency has sought in recent weeks to show it is cracking down on safety concerns.
NHTSA is looking at three Toyota recalls for gas-pedal and sudden-acceleration reports. Regulators are looking into consumer complaints that allege 34 deaths related to Toyota sudden-acceleration problems.