(Reuters) - Toyota Motor Corp (>> Toyota Motor Corp) cars won in six of the 19 categories in an annual auto industry reliability survey published on Wednesday, while Fiat Chrysler Automobiles trailed in the bottom three of the report's main rankings.

Consultancy J.D. Power's closely-watched 2018 U.S. Vehicle Dependability Study, put Toyota ninth overall and its Lexus luxury vehicle division first in the survey of owners of three-year old cars.

Overall the study showed a 9 percent improvement in vehicle dependability from 2017, the first time the industry-wide score has improved since 2013.

"Strong dependability scores not only improve demand for used vehicles, but also are a contributor to higher residual values," Jonathan Banks, Vice President of Vehicle Analysis and Analytics at J.D. Power said.

"Improving dependability ultimately supports new vehicle sales and provides a better perception of the brand."

Lexus topped the rankings for a seventh consecutive year with a score of 99 problems per hundred cars, compared to 127 for Toyota overall.

Porsche was a close second with 100 problems per hundred and Buick third with 116 — the strongest performance for dependability among mass-market brands.

The study measures the number of problems experienced per 100 vehicles during the past 12 months by original owners of 2015 model-year vehicles, with a lower score reflecting higher quality.

The survey also said that, while FCA was the third worst rated overall with 192 problems per hundred, Fiat was also the most improved.

"All FCA US brands improved their scores year-over-year in J.D. Power's 2018 Vehicle Dependability Study, with the exception of the Chrysler Brand," FCA U.S said in a statement.

"The Chrysler Brand's ranking is primarily attributed to a launch year of the Chrysler 200, which is no longer in production."

The study is based on responses from 36,896 original owners.

(Reporting by Sanjana Shivdas in Bengaluru; editing by Patrick Graham and Shounak Dasgupta)

Stocks treated in this article : Toyota Motor Corp, Fiat Chrysler Automobiles