Trouble with new technologies including a clunky control system for its radios pounded Ford Motor Co's ranking in a closely watched quality ranking, just a year after the U.S. brand led its mass-market rivals.

In a reversal of fortune, Japanese automaker Toyota Motor Corp's <7203.T> namesake brand, which last year tumbled to its lowest ranking ever due to a series of damaging recalls, pulled off a corresponding rebound, according to the influential study of U.S. consumers released on Thursday by J.D. Power and Associates.

Ford, the only U.S. automaker to avoid bankruptcy and a government bailout, saw its namesake brand slide to 23rd -- its lowest spot in a decade, down from 5th place last year, which represented, its highest ranking ever. Toyota rebounded to 7th from 21st last year.

Ford is on the leading edge, certainly in the mass market, of trying to bring new technology into the vehicles, said David Sargent, J.D. Power's vice president of global vehicle research. With that comes some risk that there will be unforeseen problems and that's exactly what happened.

There's a great deal of parity between the different vehicles and different brands, so if you have a significant problem in a particular area, that can really set you back in terms of the rankings, he added.

Toyota's Lexus luxury brand captured the top spot, moving up from 4th last year.

The J.D. Power study, which records difficulties faced by new car owners in the first 90 days of ownership, was conducted between February and May of this year.

The results of the survey, the most comprehensive benchmark of new car quality, are used heavily in auto industry marketing and are seen as influential in shaping consumer perceptions. It is also watched as a barometer for resale values and as a proxy for warranty costs.

REBOOT A CAR?

Ford customers found the automaker's audio and interior control systems too complex or at times inoperable, Sargent said: It's not as easy to reboot a car as it is a computer.

Mark Fields, Ford's president of the Americas, said on Tuesday ahead of the survey's release that the company's own quality ratings would be mixed for the year.

Ford was dinged earlier this year when influential magazine Consumer Reports did not give a recommended rating to its SUVs Ford Edge and Lincoln MKX because of the complexity of the MyFord Touch and the MyLincoln Touch systems.

Ford has acknowledged those problems, making software changes and offering customers training at Ford dealers. It also said Tuesday it is working to ease the use of voice-control systems in its vehicles and making improvements on a few of its powertrains.

As we see issues in our own internal reporting, we jump all over them and quickly address them, Fields said.

Ford, whose F-150 pickup truck ranked No. 6 overall ahead of Toyota's Tundra truck at No. 12, reiterated on Thursday it moved quickly to address consumer complaints and quality was back on track.

On average across the industry, U.S. consumers reported 107 problems per 100 vehicles sold, an improvement from 109 problems last year and an all-time best performance in the study's 25-year history.

However, the industry average for all-new or heavily redesigned vehicles slid 10 percent to 122 problems per 100 vehicles, J.D. Power said. The decline was most stark in the engine and transmission, as well as audio, entertainment and navigation categories.

Software to improve fuel efficiency sometimes leads to engine or transmission hesitation when accelerating or changing gears, J.D. Power said.

Meanwhile, problem rates in the audio and entertainment category jumped 18 percent as many consumers complained their hands-free or voice-activation systems were not intuitive or did not always function properly.

U.S. automakers in recent years have spent heavily in a bid to close the gap with the Japanese automakers, led by Toyota and Honda Motor Co <7267.T>, which had established a reputation for eliminating flaws from engineering and manufacturing. However, after finishing on average ahead of the import brands for the first time ever last year, they trail again this year.

General Motors Co's Cadillac luxury and GMC truck brands were the only ones among U.S. automakers to exceed the industry average, coming in at the 9th and 10th places. Only the top 10 brands in the survey topped the industry average.

GM's Chevrolet and Buick brands ranked 14th and 20th among the 32 brands measured. Ford's Lincoln brand finished 17th, while Chrysler's namesake, Ram, Jeep and Dodge brands ranked 16th, 22nd, 25th and 32nd, respectively.

(Additional reporting by Bernie Woodall in Detroit, editing by Dave Zimmerman)

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