NORWALK, Calif. (AP) _ A jury found Hyundai Motor Co. negligent in the design of seat belts used on some cars and ordered the automaker to pay $15 million to a boy left blind and unable to talk or walk after a crash.

The Superior Court jury on Monday found that the seat belt design in a 1988 Excel - consisting of a shoulder restraint but no lap belt - was defective and that the automaker failed to warn consumers of the danger to children.

Hyundai contended the shoulder restraints, which were on some cars sold in 1987 and 1988, met federal safety standards, and the company plans to appeal.

The case stemmed from a 1990 accident involving Adam Ketchum, who was 9 at the time. He was sitting in the front seat of his mother's Excel, wearing the belt, when she drove into the back of a tractor-trailer.

The belt compressed the boy's neck, cutting off oxygen to the brain and causing permanent brain damage, said his attorney, Mark Robinson Jr.

The seat belt system has been shown in crash tests to be harmful to shorter adults but was never tested with child-size dummies, Robinson said.

The car included a warning that the restraint could cause neck irritation to short adults and children.

''We believe that the two-point seat belts are not defective,'' said Dotty Diemer, a spokeswoman for Hyundai Motor America in Fountain Valley. ''We are not recalling the vehicles.'' She said the company had documented the safety of the belts.

Some 92,500 Hyundai cars sold in the United States in 1987 and 1988 had the shoulder-belt-only design. The design was on 10 percent of the cars sold here in '87 and a quarter of the cars in '88, Diemer said.

The jury awarded the boy $13 million for lost earning potential and $2 million for pain and suffering.