Tesla's Autopilot feature was connected to hundreds of crashes: investigation

• Feds are investigating whether Tesla's 2023 Autopilot recall worked.
• In December, Tesla recalled 2 million Autopilot-equipped vehicles with a software update.

Tesla recalled more than 2 million vehicles last year over crashes involving its Autopilot program.

But did the recall work? Crashes kept happening, the feds say, and now they're investigating.

The National Highway Traffic Safety Administration (NHTSA) said Friday it's opening up a fresh probe over the "crash events."

An additional report was also released Friday by the regulator offering up more details into issues investigated prior to the recall. In the report, the NHTSA said it investigated 956 Tesla crashes between January 2018 and August 2023, where Autopilot was involved — 29 of which resulted in fatalities.

Tesla recalled the vehicles last year to fix Autopilot with an over-the-air software update after regulators said the driver-assist tech wasn't doing enough to stop driver misuse.

As part of its new investigation, the NHTSA will use tests of the recalled vehicles and look into why Tesla's fix made owners opt-in, making it something that could be "readily reversed."

Tesla also sent later updates to Autopilot that weren't a part of the recall, the NHTSA said.

"This investigation will consider why these updates were not a part of the recall," the agency wrote.

Tesla did not immediately respond to a request for comment from Business Insider.

The EV brand has been struggling with flagging sales and reported burning through cash in its latest earnings report. Still, the stock soared after CEO Elon Musk made big promises about two new products: more affordable cars and the company's foray into self-driving robo-taxis.

It's not clear how regulators will react to Tesla's fleet of ride-hailing vehicles when — or if — they arrive.