A two-year study looking for possible causes behind Toyota’s rash of unintended acceleration issues has put primary blame on driver error — but the review by the National Academy of Sciences also cautioned that some problems may have been caused by inadvertent interactions involving vehicle electronics — an issue frequently cited by the automaker’s critics.

Though there was no hard evidence of specific electronic defects, the 139-page report cautioned that “the absence of evidence is not the evidence of absence.” Warning electronic faults may be “untraceable,” it calls for stricter government involvement in setting standards for the use of electronic control vehicle systems, reported msnbc.com.

The new report completes a series of studies set in motion by the National Highway Traffic Safety Administration which, in March 2010, asked both the NAS’s National Research Council, as well as NASA, to see why there were so many complaints about what the media was referring to as “runaway Toyotas.”

The problem first made headlines in the summer of 2009, when a California Highway Patrol Officer and several members of his family were killed in a fiery crash involving a Lexus they had borrowed. The maker initially recalled several million vehicles due to a problem it described as “carpet entrapment,” but in January 2010 it added millions more due to a potentially sticky accelerator linkage.

Ultimately, more than 8 million Toyota and Lexus vehicles were recalled in the U.S. alone. But the NHTSA received numerous additional complaints — with plaintiffs’ attorneys lining up to file lawsuits against the automaker — alleging some unknown electronic gremlin was also at work.

Last February, the NASA panel issued its report, contending it had found no indication of electronic defects. The National Research Council study echoes that, putting the primary blame on driver error. That had been the conclusion of other investigators in a number of instances — in one, police investigators found that a woman driver involved in a crash had been pressing on the gas pedal, rather than the brake, so hard she had bent its linkage.

Nonetheless, the latest study does not rule out electronic issues, which it cautioned can result in “untraceable faults,” with no physical evidence — other than a crash — to show when there might have been a problem such as a momentary software glitch.

“Some failures of software and other faults in electronics systems do not leave physical evidence of their occurrence, which can complicate assessment of the causes of unusual behaviors in the modern, electronics-intensive automobile,” the report cautioned.

Nonetheless, Louis Lanzerotti, the chairman of the panel and a New Jersey Institute of Technology physics professor, said during a conference call that, “All the data available to us indicated the conclusion that there was no electronic or software problem” that may have caused the Toyota unintended acceleration reports.”

The new study called for a number of steps to be taken to reduce the likelihood that electronic hardware and software do cause problems in the future – a critical issue considering the increasing use of digital technology in modern automobiles. Among the recommendations:

• NHTSA should convene an advisory panel to set uniform industry testing standards for electronic systems;
• New vehicles should be equipped with aircraft-style black boxes to make it easier to trace and identify defects;
• Regulators need to continue research on pedal design and placement.
The study also called for closer cooperation between NHTSA’s researchers and the Transportation Department’s Office of Defect Investigations.

While some critics questioned the latest study — as they did earlier NHTSA and NASA findings, Transportation Secretary Ray LaHood said that in his eyes the latest report “does close the book” on the Toyota scandal.

At one point, following the second unintended acceleration recall, LaHood had said owners of Toyota vehicles involved in the recalls might think about parking those products until they were repaired.

The NHTSA ultimately levied a series of record fines against Toyota, including one for $33 million for delaying action on the sticky accelerator problem.

The maker, long known for seemingly bullet-proof quality, also recalled products in 2009, 2010 and 2011 for a variety of other issues, ranging from electronic brake issues with its Prius hybrid to excessive corrosion that could cause metal parts to fell off while driving the Sienna minivan.

As a result, Toyota had more recalls than any other maker in the U.S. market in 2009 and 2010, and with 3.5 million vehicles involved in service campaigns in 2011, came in just behind Honda, which last year recalled 3.7 million vehicles.

The long-term impact to the company’s reputation is unclear. Toyota — along with Honda — was one of only two major makers to suffer a sales decline in 2011. Analysts put most of the blame on the March earthquake and tsunami that severely limited global production for much of the year, but they also note cool consumer response to the latest update of the Toyota Camry at the same time as competitors like Ford are becoming increasingly aggressive in market segments long dominated by Toyota.

A new study by KBB.com shows that Toyota has regained its long-standing position as having the highest loyalty rate in the industry. But the maker is still heavily dependent on “conquesting” buyers from other brands. That, many analysts warn, could become more difficult in light of the hits Toyota’s reputation has taken.

Toyota Motor Corp. scored a victory in 2011 as U.S. deliveries of its Prius v wagon in 10 weeks topped sales of General Motors Co.’s Chevrolet Volt plug-in hybrid that was available all year.

Toyota sold 8,399 of the hybrid wagon, which didn’t arrive at U.S. dealerships until the last week of October, said Carly Schaffner, a spokeswoman for the company. GM delivered 7,671 rechargeable Volts in 2011 and 7,997 in the model’s first 13 months on the market. The Japanese automaker hadn’t distinguished Prius v sales from those of the original one, reported Bloomberg.

“Prius v is off to a great start,” Jim Lentz, president of Toyota’s U.S. sales unit, said in an e-mail this week. The hybrid wagon starts at $26,400, Toyota said on its website. The Volt starts at $39,145 and is eligible for as much as $7,500 in federal tax credits.

Toyota, the largest gasoline-electric auto seller, wants to deliver more than 220,000 vehicles bearing the Prius name this year to U.S. customers, a 60 percent increase from 2011. That’s to be fueled by a four-car “family” consisting of the original hatchback, the v, the Prius c subcompact arriving in March, and a plug-in Prius that goes about 15 miles on battery power.

GM missed its goal of selling 10,000 Volts last year. A slow production increase kept dealers for the Detroit-based company in short supply until December, and a federal investigation of three fires that occurred after Volt crash tests lowered demand for the car, according to Bandon, Oregon- based CNW Marketing Research Inc.

Comparing the plug-in Volt with the hybrid wagon is “ridiculous,” said Rob Peterson, a GM spokesman.

“Consumers cross-shop vehicles with comparable technologies or functionality, not a new name plate,” Peterson said by e-mail. “Comparing Volt to Prius v is apples and oranges.”

The range of alternative-power autos available to U.S. drivers is mushrooming as manufacturers offer vehicles powered wholly or in part by electricity, bio-fuels, natural gas and even hydrogen. That number will jump this year with new offerings required to meet clean air rules in California.

Bloomberg News tracked sales of 37 such vehicles in 2011, up from only two in 2000. Offerings include the Prius, the Volt, Nissan Motor Co.’s Leaf and Honda Motor Co.’s FCX Clarity fuel- cell sedan leased in California.

Hybrid sales accounted for only 2.2 percent of U.S. auto sales last year, down from 2.4 percent in 2010, according to researcher LMC Automotive. The decline was a result of reduced production of the Prius, which accounts for half of all hybrid sales, after Japan’s natural disasters cut the supply of parts, said Lentz, who is based at Toyota’s U.S. sales office in Torrance, California.

The March 2011 earthquake and tsunami temporarily halted Prius assembly in Japan, leaving U.S. dealers with little inventory of the car for months. Overall Prius sales fell 3.2 percent last year to 136,463.

Toyota dealers in the U.S. also sold 9,241 hybrid midsize Camry cars, 37 percent fewer than in 2010, according to Autodata Corp., and the Toyota City, Japan-based automaker said it delivered 14,381 Lexus CT200h gas-electric compact luxury wagons in the model’s first calendar year.

Nissan sold 9,674 Leaf all-electric cars in the U.S. last year, missing its target of 10,000 to 12,000. The company said production lost to the tsunami limited availability. The Leaf averages about 73 miles per charge, according to the U.S. Environmental Protection Agency.

The Prius v wagon, larger and heavier than a standard Prius, averages 42 miles per gallon of gasoline in combined city and highway driving, compared with 50 mpg for the main version. The Volt, capable of going 35 miles on battery power, has two U.S. fuel-economy ratings: 94 mpg-equivalent when both its lithium-ion pack and gasoline engine are used, and a combined 37 mpg when powered solely by gasoline.

Toyota Motor Corp. survived a massive recall two years ago and the effects of Japan’s tsunami last year. Now the company faces an unprecedented rush of competitors for its franchise car, the Camry family sedan.

The Camry, the best-selling mid-size car in the U.S. for the past 10 years, faces new family-sedan competition this year from Honda Motor Co., Nissan Motor Co., Ford Motor Co. and General Motors Co. Volkswagen AG, Hyundai Motor Co. and Kia Motors Corp. have raised production of their family cars, making the market even more competitive, according to Bloomberg.

Add it all up and the mid-size car market is as tough as it has ever been, even for a dominant franchise like the Camry. Family cars represent 15 percent of the U.S. market and a vital way to reach new buyers and keep them in their brands for years beyond the first purchase.

“There has never been anything like this before,” said Jeremy Anwyl, vice chairman of Edmunds.com, an automotive research website based in Santa Monica, California. “We have had competitive races with two or three new models, but not seven or eight competitive cars fighting it out.”

This year, Ford brings out its new Fusion sedan, with two hybrid versions of the car. GM’s top-selling Chevrolet division started delivering the redesigned Malibu this month. Honda showed off a coupe version of its Accord at the Detroit auto show this week and will sell the new car later this year. Nissan has a new Altima coming as well.

On top of that, Kia has added a third shift to its U.S. plant to increase production of the Optima sedan. Hyundai last year boosted production at its Montgomery, Alabama, plant to 10 percent more than its official capacity. Volkswagen is now up to full output at its $1 billion Chattanooga, Tennessee, factory that began producing Passat sedans last spring.

“We haven’t seen anything like this since back in the ‘90s, when Ford made a push with the Taurus,” said Jim Lentz, president of Toyota’s U.S. sales arm.

Mid-size car production in North America may rise 15 percent, or 305,000, to 2.4 million vehicles this year, according to a forecast from LMC Automotive, a research firm based in Oxford, England. Most of those cars stay in the U.S., where sales are expected to rise by 100,000 to 200,000 vehicles, said Jeff Schuster, senior vice president with LMC.

“There will be pricing pressure,” Anwyl said. Carmakers used to be able to rely on keeping prices up and avoiding incentives for a year or more with a new model, Anwyl said. With this kind of competition, carmakers may have as little as three months before discounts are needed, he said.

Ford has big ambitions for the new Fusion. The Dearborn, Michigan-based automaker is adding a shift of workers to make the car at a factory in nearby Flat Rock, adding to the two shifts of workers building it in Hermosillo, Mexico. Sales of the Fusion rose 37 percent from two years earlier to 248,067 last year, Ford reported. The new hybrid version will get 47 mpg in the city, up from 41 for the previous one. The Camry hybrid gets 43 mpg in city driving.

“Fusion last year set a sales record, and with this new family of vehicles, we believe we can build on that success,” Chief Executive Officer Alan Mulally said Jan. 9 when asked if Fusion can be the top selling mid-size car. “I think we really will be preferred in that” mid-size car segment.

GM is also adding production by using its Chevy Volt plant in Detroit as a second source of Malibus, in addition to the primary factory in Fairfax, Kansas.

With so many new models entering the family-car market, it will be a challenge for anyone to stand out, said Joel Ewanick, GM vice president and chief marketing officer. Chevy will offer an Eco version of the Malibu that can get 37 mpg on the highway with a small, inexpensive electric motor and battery mated to a 4-cylinder engine.

Honda said it hopes to sell more than 300,000 Accords in the U.S. this year, which would be a 27 percent jump over 2011. The increase will come from both the current Accord and the redesigned model due in the second half, said John Mendel, executive vice president of the company’s U.S. sales unit.

Mendel said that fresh styling and new engines and transmissions will bring Honda back after production cuts forced by the Japan tsunami in March caused losses in market share.

“A few people have taken us to task and enjoyed our absence from the market,” Mendel said in an interview in Detroit. “I think we’re going to enjoy being back.”

Honda could be hurt in the family-sedan market because the new Camry was introduced in the fourth quarter while the new Accord is still months away, said Mike O’Brien, Hyundai’s vice president for U.S. product development.

“In terms of model cycles, Toyota realizes this is their year to capture share from Honda because Accord is old and Camry is new,” O’Brien said in a Jan. 11 interview. “There’s going to be a big battle between those two, and there is going to be collateral damage. Toyota is going to be very aggressive on marketing.”

The company is determined to keep its top spot.

“It will be a heated segment in the industry, but we’re extremely confident about the new Camry,” said Bob Carter, general manager of Toyota brand sales in the U.S. “Mark my words: One year from now, Camry will repeat as the best-selling car in America for an eleventh consecutive year.”

Toyota Motor Corp.’s December sales gain beat analysts’ estimates and Kia Motors Corp. had the biggest increase among Asia-based brands, capping the U.S. auto industry’s best year since 2008.

Sales rose 0.4 percent from a year earlier for Toyota, compared with the average 1 percent drop of five estimates compiled by Bloomberg. Deliveries increased 43 percent for Kia, 13 percent for affiliate Hyundai Motor Co. and 7.7 percent for Nissan Motor Co., according to statements yesterday. Honda Motor Co. reported a 19 percent drop, citing tight inventory.

Industrywide sales gained an estimated 8.7 percent as consumer confidence reached an eight-month high in December, and carmakers aired holiday ads and continued promotions begun in November. Kia’s December surge in the U.S. gave the Seoul-based company a 36 percent full-year increase, the largest for a major automaker.

“Kia has even more potential this year,” said Rebecca Lindland, a Norwalk, Connecticut-based analyst for IHS Automotive. “Our forecast is for them to be up 23 percent. Hyundai will be up by double digits again in 2012, but right now everything new from Kia is selling really well.”

Japan’s rebound is a double-edged sword for Toyota Motor Corp.

This should be the year for the auto maker to shake off natural-disaster-related supply constraints from 2011 and its 2010 recall woes, reclaiming lost U.S. market share. Already, industry figures out Wednesday are expected to show Toyota improving its share in December by perhaps the most of any auto maker, even as industry sales are flat or weaker from November’s annualized level. Still, with a current market share of roughly 14 percent, Toyota has a ways to go before it gets back to its peak 17 percent levels, reported The Wall Street Journal.

There is some doubt as to whether those levels can be recaptured in the wake of the company’s massive recalls. What is certain is that the steely Japanese yen isn’t helping Toyota’s prospects. For reasons ranging from a Japanese recovery to dimming growth prospects elsewhere, the yen has recently become one of the world’s strongest currencies—much to the chagrin of Japan’s exporters, which are critical to the island nation’s economy.

The yen has risen by some 17 percent against the dollar over the past two years, even as Japan has repeatedly intervened to stem the rise. Toyota isn’t the only Japanese auto maker struggling with the surging yen when it comes to exported vehicles; Honda and Nissan also are feeling the impact. But of the three, Toyota retains the largest Japanese production base, meaning its costs are most sensitive to yen appreciation, notes Credit Suisse analyst Christopher Ceraso.

As Morningstar points out, each one-yen rise against the dollar is about a 32 billion yen ($417 million) hit to Toyota’s operating income—more the double the impact on Honda. Moreover, at current levels of roughly 76 or 77 yen per dollar, Japan’s output of vehicles like compact cars for the U.S. market is rendered unprofitable. For Toyota, the hope is such yen strength will prove temporary; indeed, the auto maker is planning to boost production 24 percent globally next year as its sales gather pace.

The yen may prove stubbornly buoyant, however, unless global growth prospects suddenly revive. And this may keep Toyota’s earnings—and shares—from reaping the full benefit of that rebound. In 2011, Toyota proved a better bet than General Motors or Ford Motor Corp. This year, the opposite may be true.

Toyota Motor Corp. has a tradition of self-reliance. Chief Executive Officer Akio Toyoda is beginning to change that.

Toyoda agreed this month to equip some Toyota cars with Bayerische Motoren Werke AG diesel engines, building on an earlier deal to use Tesla Motors Inc. battery packs in future electric vehicles. Before the grandson of the founder became president, Toyota had not purchased such core technologies from other carmakers, said Shiori Hashimoto, a spokeswoman at the Toyota City-based carmaker.

The alliances illustrate how Toyoda is shaking up decades-old practices at Japan’s largest manufacturer, which is poised to cede its three-year lead in the global automotive industry to General Motors Co. The company is emerging from three years of crisis management — from millions of vehicles recalled to coping with Japan’s biggest postwar natural disaster, according to The Detroit News.

“They have a high need for control, because they want a high level of confidence things will be delivered on time,” said Jeff Liker, an engineering professor at the University of Michigan in Ann Arbor specializing in Toyota research. “When you go outside the family, there’s some risk. Akio is willing to take that risk.”

The worldwide recalls in 2009 and 2010 created an opportunity to push changes in Toyota’s corporate culture, Liker said. The CEO likely “came to the conclusion Toyota has grown too insular in Japan, that it needed to open up more, get more access to the outside world,” he said.

Toyoda has reason to drive change. The company forecasts profit will fall to 1 percent of revenue this fiscal year, Toyota’s second-lowest margin, based on data compiled by Bloomberg stretching back to 1992.

At its height in the mid 2000s, the carmaker was generating margins of almost 7 percent. The stock is down about 70 percent from its peak in February 2007.

“Toyota used to be able to grow simply by manufacturing the cars it made best, but now it needs to make gasoline and diesel cars, hybrids and electric vehicles,” said Mitsushige Akino, who oversees about $600 million at Ichiyoshi Investment Management Co. in Tokyo. “If Toyota doesn’t reach out to other companies for help in technology, they won’t be able to sustain market share.”

Under this month’s agreement, Toyota will equip some of its European models with BMW engines starting in 2014 to gain market share in the region, where most cars run on diesel.

Toyota’s share of European auto sales was 3.8 percent this year through October, according to the European Automobile Manufacturers’ Association. By comparison, Toyota’s U.S. share was 12.7 percent through November, according to Autodata Corp., based in Woodcliff Lake, N.J.

In May 2010, Toyota agreed to use Tesla’s lithium-ion battery pack and motor on its RAV4 sport-utility vehicle starting early next year. Toyoda said at the time that he hoped the partnership would also inspire Toyota workers to adopt the “venture business” spirit of Tesla.

The BMW and Tesla deals differ from previous partnerships because Toyota is the recipient of another company’s technology, Hashimoto, the Toyota spokeswoman, said. In previous deals such as a project to develop a hybrid system for trucks with Ford Motor Co., and others with GM, Aston Martin and Fuji Heavy Industries Ltd.’s Subaru, Toyota either provided or co-developed technologies, she said.

Only the BMW accord is likely to yield direct benefits for the Japanese carmaker because the other agreements are “small, isolated deals,” said Maryann Keller, an auto analyst and president at Maryann Keller & Associates.

The project with Palo Alto, California-based Tesla, for example, isn’t likely to change Toyota’s management practices because “you cannot change a corporate culture simply by working with a company that’s 3,000 miles away,” she said.