WASHINGTON - Toyota Motor Corp promised a quality shake-up and apologized for safety mistakes that it blamed on rapid growth, as two days of congressional hearings crucial to the automaker's reputation got under way on Tuesday.

President Akio Toyoda said he was deeply sorry for accidents caused by safety problems with Toyota vehicles and detailed a set of reforms that would shift control of recall decisions away from the automaker's Japanese headquarters.

The congressional hearings are critical for the world's largest automaker as it seeks to repair damage over unintended acceleration and braking problems that have led to the recall of more than 8.5 million vehicles around the world.

We pursued growth over the speed at which we were able to develop our people and our organization, and we should sincerely be mindful of that, Toyoda said in written testimony.

Toyota's recent safety problems revolve around sticky accelerators, accelerators that can be pinned down by loose floor mats and a braking glitch affecting its hybrid models.

But many lawmakers, some Toyota owners and others fear Toyota's current recalls do not cover all complaints of runaway acceleration and also want reforms at the National Highway Traffic Safety Administration.

Rhonda Smith, driver of a Toyota Lexus in a 2006 incident where her car reached 100 mph, told lawmakers on Tuesday she felt Toyota and NHTSA had dismissed her belief that the vehicle's electronics were to blame.

Shame on you, Toyota, for being so greedy. And shame on you, NHTSA, for not doing your job, Smith told the House Energy and Commerce Committee panel.

Toyota's top-ranking U.S. executive, Jim Lentz, arrived for Tuesday's hearing in a silver 2010 Toyota Highlander SUV, one of the vehicles subject to the sticky accelerator recall.

We now understand that we must think differently when investigating complaints and communicate faster, better and more effectively with our customers and our regulators, Lentz said.

U.S. Transportation Secretary Ray LaHood said he would hold Toyoda to his assurance that the carmaker is working to address all safety issues.

MOST DIRECT APOLOGY

Toyoda, grandson of Toyota's founder, will testify on Wednesday before the House Oversight and Government Reform committee, where he is considered the star witness.

In his written testimony, Toyoda apologized to the surviving family of Mark Saylor, an off-duty California Highway Patrol officer, who was killed along with three members of his family last August.

The remarks marked the most personal and direct apology from Toyoda, who has appeared uncomfortable with the media spotlight and had initially resisted calls to testify before congressional investigators.

He also said future recall decisions would no longer be made solely by engineers in Japan, that outside advisers would be consulted.

The unintended acceleration problems with Toyota vehicles have been linked to at least five U.S. deaths, with 29 other fatality reports being examined by U.S. authorities.

Several lawmakers at Tuesday's hearing criticized Toyota's resistance to probing whether its electronic throttle systems can suffer from electromagnetic interference (EMI).

Toyota's leadership has been ambiguous about whether these two recalls fully account for and address the problem of sudden unintended acceleration, said Rep. Bart Stupak, the Michigan Democrat who chairs the oversight and investigations subcommittee.

Henry Waxman, the California Democrat who chairs the full commerce committee, called for fundamental reforms to Toyota's leadership and said reforming the NHTSA would require legislation.

There is no evidence that Toyota or the government agency NHTSA took a serious look at the possibility that electronic defects could be causing the problem, Waxman said.

He said Toyota did not initiate a study into possible electronic defects until two months ago and NHTSA does not have an electrical or software engineer on staff.

But several Republicans on the committee cautioned that Toyota should not be subject to an unfair grilling. I don't believe that we should go on a witch hunt, said Joe Barton, the ranking Republican on the full committee.

Texas Republican Michael Burgess said U.S. government ownership of General Motors posed an inherent conflict of interest in assessing Toyota.

The U.S. Treasury assumed a majority stake in GM last year in return for bailout money and bankruptcy financing assistance.

PR DISASTER

Aaron Bragman, an analyst at IHS Global Insight, said the situation looked likely to get worse this week for Toyota.

From a public relations standpoint, this has been an unmitigated disaster from the start for Toyota, handled poorly by a team unfamiliar with major public relations catastrophes, Bragman said.

Adding to the Japanese automaker's deepening crisis, new documents surfaced over the past two days which detailed how Toyota beat back U.S. safety regulators' efforts for a wider probe in 2007.

Mike Jackson, chief executive of AutoNation Inc, was one of several hundred Toyota dealers and workers who came to Washington on Tuesday as part of a campaign organized by the automaker to help win back popular and political support.

I'm certain that once the vehicles have been repaired and production has resumed that going into March and April, that (Toyota's) sales will recover, Jackson told Reuters Insider.

In the wake of Toyota's massive recall, Consumers Union, the nonprofit publisher of Consumer Reports, issued a call on Tuesday for urgent changes to strengthen U.S. auto safety regulation.

It said that the U.S. safety regulatory system should be reformed to become more transparent and that the National Highway Traffic Safety Administration should have more funding and the ability to impose tougher sanctions.

Toyota's U.S. shares were down 1.8 percent at $71.65 on the New York Stock Exchange in afternoon trading Tuesday, down more than 21 percent from their 12-month high reached last month.

(Additional reporting by Chang-Ran Kim and Kevin Krolicki; writing by Tim Dobbyn, editing by David Holmes, Dave Zimmerman and Matthew Lewis)

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