The National Highway Traffic Safety Administration indicated that there were no deaths linked to the defect. But NHTSA acknowledged that it is aware of last week's death of "Star Trek" actor Anton Yelchin in an accident the agency said "may have been related to the alleged defect."

The company in April recalled 1.1 million vehicles worldwide, some 811,000 of them in the U.S. market.

Injuries and crashes outside the United States were not reported by U.S. safety officials.

Yelchin, 27, was killed June 19, crushed when a 2015 Jeep Grand Cherokee rolled backward on the steep driveway of his Los Angeles home, pinning him against a brick wall and a fence.

The safety regulator's closing report to an investigation that began in February was dated June 24 and placed on the NHTSA website Tuesday. NHTSA said Los Angeles police and FCA were investigating the actor's death.

While not acknowledging a design flaw in its transmission gear selectors, FCA has said rollaways have occurred because drivers mistakenly believe they had placed the vehicles in park before getting out.

NHTSA said there have been 686 complaints linked to the recalled models, which include 2014-2015 Jeep Grand Cherokee, and 2012-2014 Dodge Charger and Chrysler 300 with 3.6-liter engines.

NHTSA says affected vehicles have gearshift controls with "an unfamiliar movement that does not provide the tactile or visual feedback that drivers are accustomed to receiving from conventional shifters."

The recalled vehicles sound warning chimes and alert messages if the driver's door is opened, the engine running and "park" not selected on the gear shifter. FCA says it will enhance the warning system and install computer software that will automatically place the transmission in "park" if a driver fails to do so and opens the driver-side door.

Last week, FCA said it would speed the recall of the 1.1 million vehicles, with the first fixes within days. FCA had initially said its 2,400 U.S. dealers would install the fixes in the fourth quarter.

In California last Friday, Jeep Grand Cherokee owners filed suit against FCA.

Last week, FCA added 13,000 Maserati models to its U.S. rollaway recall.

(Reporting by Bernie Woodall; Editing by Jeffrey Benkoe, Chizu Nomiyama and David Gregorio)

By Bernie Woodall