Updated at 4:41 p.m. ET
Toyota is recalling nearly half a million cars, most of them large sedans sold in the U.S., for problems that can cause the steering wheel to lock up. It's the latest indication that the automaker is still struggling with vehicle problems even as it works to overhaul quality control.
The recall, announced Thursday, affects 412,000 vehicles in the U.S. - 373,000 Avalon sedans and 39,000 Lexus LX 470 SUVs. The recall is Toyota's largest since announcing it would fix 600,000 Sienna minivans over rusting spare tire holders in April.
Toyota has been embroiled in its recall crisis since October, when it announced a recall of 5.3 million cars and trucks to fix floor mats that can trap pedals and cause unintended acceleration. A number of recalls have followed, from sticky gas pedals to braking problems with the Prius hybrid to rusting frames in the Tacoma pickup.
Thursday's announcement brings the size of Toyota's recalls to about 9.5 million cars and trucks since October.
"I don't think it's going to end anytime quickly or easily," said George Magliano, auto analyst with the consulting firm IHS-Global Insight, of the company's recalls. "Toyota had this big run of growth. The more they grew volume and market share, the more this (quality) system started to develop cracks."
The Avalons recalled in the U.S. range from the 2000 model year through to 2004 and have improper casting of the steering lock bar - the component that locks the steering wheel when the vehicle is shut off - that can cause a crack to form on the surface.
Over time, the crack can expand, which can cause the steering wheel to become difficult to unlock when stationary. In some circumstances, the problem can cause the steering wheel to lock up during driving, Toyota said.
Three unconfirmed accidents with no injuries have been reported because of the problem, Toyota said. It will fix the Avalon steering problem by replacing a part called the steering column bracket, which houses the lock bar.
For the Lexus LX 470, Toyota is recalling the 2003-2007 model years to fix a different steering shaft problem, which could cause loss of steering control. No accidents have been reported from the problem, the company said.
For both repairs, customers will begin receiving letters in August asking them to bring their cars to dealers.
The LX 470 problem also affects 9,670 vehicles in Japan, two Land Cruiser models. Toyota is recalling another 6,750 vehicles in Japan, a sedan called the Pronard, for a problem similar to that experienced by the Avalon.
Toyota has been working to overhaul its quality control after being criticized for its slow response to vehicle flaws. It is hiring thousands of engineers to check for problems and appointing chief quality officers in its major regions.
"Toyota is continuing to work diligently to address safety issues wherever they arise and to strengthen our global quality assurance operations," said Steve St. Angelo, Toyota chief quality officer for North America.
Toyota was slapped with a record $16.4 million fine in the United States for failing to promptly tell the government about its car defects. It remains under investigation by a federal grand jury in New York and by the Securities and Exchange Commission.
The company also faces more than 200 lawsuits in the U.S. tied to accidents involving defective automobiles, the lower resale value of Toyota vehicles, and a drop in its stock value.
© 2010 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.