Zoox, the self-driving unit of Amazon, is recalling 258 autonomous vehicles after a U.S. safety investigation found that its automated driving system could trigger unexpected hard braking, according to a company filing on Wednesday.
The recall applies to Zoox vehicles running software versions released before November 5. The California-based company stated it has already resolved the issue by deploying an over-the-air software update to its fleet.
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The U.S. National Highway Traffic Safety Administration (NHTSA) launched an investigation into Zoox’s autonomous vehicles in May, following two rear-end collisions in which sudden braking led to injuries for motorcyclists. The company disclosed that its software update addressed two specific concerns: excessive braking when a bicyclist was in or near an adjacent crosswalk as a traffic light turned green, and unnecessary hard braking when a motorcyclist or bicyclist rapidly approached from behind.
Zoox reported no further incidents and said it was proceeding with the recall “in light of NHTSA’s position and in the interest of promoting transparency.”
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The recall comes as self-driving vehicle companies face increasing regulatory scrutiny. Zoox has been expanding its autonomous vehicle testing in new cities, but industry concerns persist following high-profile incidents. General Motors’ Cruise and Google’s Waymo have both faced regulatory challenges, including a serious pedestrian injury involving a Cruise vehicle in 2023. Waymo also recalled more than 670 self-driving cars last year after one struck a utility pole in Phoenix, Arizona.
Separately, NHTSA continues to investigate Zoox’s 2022 self-certification of a robotaxi without traditional driving controls.