Tesla terminated Henkes last year, who then sued the company, claiming he was sacked for voicing safety issues. (Photo: Photo by Craig Adderley from Pexels)Federal regulators have opened an investigation into roughly 174,000 Tesla Model Y vehicles from the 2021 model year after reports that their electronic door handles may become inoperative, potentially leaving occupants unable to enter or exit the vehicle in certain scenarios. NHTSA said the issue appears to be related to insufficient voltage reaching the electronic door locks. The agency emphasized that its probe is focusing on operability from outside the vehicle, where there is no manual override available. The stock rose as much as 7.3% in premarket trading and is up more than 22% over the past 30 days.