Introduced last year with various styling tweaks and added features, the 2016 Hyundai Sonata is now being investigated by the National Highway Traffic Safety Administration.

The feds are looking into the rear brakes of these vehicles, which, according to AutoNews, may lock without any pressure applied to the brake pedal. The agency has already received several complaints from owners of the 2016 Sonatas, who reported that the rear brakes locked up during driving.

As I was accelerating onto a highway the electronic emergency brake system … without warning activated while vehicle was accelerating at speeds of over 55 mph. Brake system pulsed violently and then wheels completely locked up … causing damage to entire rear braking system“, one owner said, cited by LeftLaneNews.

Despite the serious condition surrounding the 2016 Hyundai Sonatas, which are equipped with an electronic parking brake, no reports of injuries or accidents have been submitted yet. The NHTSA will continue to investigate the matter that covers roughly 8,000 units of these vehicles, reviewing reports and deciding whether a deeper probe is required.

Hyundai’s dealers were instructed earlier this year to update the brake control software, which, due to a malfunction, could cause the rear brake pads to remain glued to the brake rotors. The automaker has yet to release an official statement.

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