WASHINGTON U.S. auto safety regulators are investigating nearly 40,000 Hyundai Ioniq 5 electric vehicles over reports of power loss that may be tied to a battery charging issue.

The National Highway Traffic Safety Administration's preliminary investigation covers 2022 model year vehicles after it received 30 consumer complaints alleging a loss of acceleration. The agency said many consumers reported a loud popping noise followed by a warning displayed in their dashboard and immediately experienced a loss of power that ranged from a reduction in acceleration to a complete loss.

NHTSA said it learned from Hyundai that the failure is related to the Integrated Charging Control Unit responsible for powering both vehicle batteries. A preliminary review indicates too much current within the unit can damage transistors, resulting in the inability to recharge the low-voltage 12V battery, NHTSA said.

Hyundai did not immediately comment.

(Reporting by David Shepardson; editing by Jonathan Oatis)