The Amazon-owned company said Friday that it has shipped to its fleet of 105 vehicles a software update that should address the issue. Zoox told TechCrunch in a statement that the software update “enhances the existing capability of detecting active [emergency] scenes by adding the ability to detect and respond to heavy smoke in certain situations.”

Nobody was on board the vehicle during the June incident, and Zoox told the National Highway Traffic Safety Administration (NHTSA) that it is not aware of injuries associated with the problem. The NHTSA’s report doesn’t state where the June incident took place, and Zoox declined to say.

Zoox’s recall comes just a week after NHTSA administrator Jonathan Morrison sent a letter to self-driving car companies warning them to stop interfering with first responders.

“Let me be clear: the inability to detect and appropriately respond to such situations represents a functional insufficiency,” he wrote. “Emergency scenes are not rare or extreme ‘edge cases.’ As such, NHTSA is today issuing a call to action for AV developers and operators to immediately focus their resources on fixing this issue.”

TechCrunch previously reported on how Waymo has had repeated run-ins with first responders as it expands into new cities. The company had at least six incidents as of March of this year in which first responders had to physically move robotaxis from an emergency scene.

NHTSA said in its report describing the recall that, on June 20, a Zoox robotaxi “encountered heavy smoke that obscured an active emergency fire scene that was not cordoned off with cones.” The Zoox vehicle “braked hard while attempting to steer away before coming to a stop.” A Zoox teleoperator was able to reverse the vehicle away from the scene, allowing first responders to place traffic cones.

Zoox told NHTSA that it conducted an investigation to determine the root cause and identify any similar incidents. The company said “this is the only event of this kind that Zoox has experienced,” and that through late June and early July, it had multiple conversations with the safety regulator about the “severity, frequency, and root causes.” Zoox decided to issue the recall on July 7, one day before Morrison’ letter.

This is not Zoox’s first recall. The company voluntarily recalled the software on its vehicles in March 2025 to resolve a hard-braking issue that NHTSA had been investigating since 2024. It issued two more recalls in May 2025 after a collision with a passenger car, and an incident where a Zoox vehicle was struck by an e-scooter rider.

Zoox has been steadily expanding its testing to new cities, and is offering free rides in Las Vegas and San Francisco, ahead of a planned commercial launch. That launch is dependent on the NHTSA granting the company an exemption to certain Federal Motor Vehicle Safety Standards, because Zoox’s robotaxis don’t have a steering wheel or pedals. The NHTSA also recently proposed removing the brake-pedal requirement for vehicles that are built to be fully autonomous.