Lexus, Porsche and Buick are the most dependable vehicle brands based on the number of problems reported by owners, according to a study released Wednesday by the consulting firm J.D. Power.

Toyota and GMC round out the top five most dependable brands. Dodge, Ford, Smart, Land Rover and Jeep are the least dependable, with the most problems reported per vehicle.

The study, now in its 27th year, questioned 33,560 owners of 2013 model-year vehicles about issues they have had in the last 12 months.

Owners were most likely to report problems with entertainment systems, navigation and phone connectivity. Those issues are growing and have lowered the entire industry’s dependability scores. Those scores are important, because buyers who are unhappy with their vehicles are less likely to buy a future vehicle from the same brand.

Auto makers are racing to add smartphone compatibility and other high-tech features to their dashboards in order to woo millennials and prevent tech companies like Apple and Google from taking over that space. But it’s been a rough ride. Auto makers’ early infotainment systems have been clunky and hard to use, especially for consumers who are accustomed to intuitive smartphones.

Brands that saw the steepest declines in their dependability scores this year — Scion, Nissan and Cadillac — all introduced new vehicles with new infotainment systems in the 2013 model year. Brands that saw the biggest improvement — Fiat, Mini and Volvo — made only minor changes to their lineups.

J.D. Power says the most common technology-related complaints are voice recognition systems that misinterpret commands and phones that don’t pair up with the car. Navigation systems that are difficult to use or inaccurate are also the subject of frequent complaints.

Renee Stephens, vice-president of automotive at J.D. Power, says auto makers have a lot of work to do to secure consumers’ trust in technology, especially as they begin wider testing of self-driving cars.

“If consumers can’t rely on their vehicle to connect to their smartphone, or have faith that their navigation system will route them to their destination, they’re certainly not yet ready to trust that autonomous technology will keep their vehicle out of the ditch,” she said.

Engine problems are the third-highest source of complaints, after technology issues and exterior issues like wind noise, road noise and rust. Uncomfortable seats and heating and air conditioning problems are also frequent problems.

Segment-level winners included the Chevrolet Malibu, which was the most-dependable mid-size car, and the Nissan Murano, which was the most dependable mid-size SUV. The Toyota Tundra was the most dependable pickup truck.

General Motors Co., the parent of Chevrolet, Cadillac, Buick and GMC, had the most segment-level winners, with eight. The Buick Encore and Chevrolet Equinox were the most dependable small and compact SUVs, while the GMC Yukon was the best performer among large SUVs.