According to the NHTSA, Waymo’s software recognized the hazard enough to slow the vehicle but then allowed it to continue forward into the standing water anyway.
WASHINGTON — Waymo has issued a safety recall of thousands of its autonomous vehicles after federal regulators determined that a software defect in the company’s self-driving system could allow robotaxis to drive into floodwater.
The defect, which affected 3,791 vehicles, caused the cars to slow down and then proceed into standing water on higher-speed roadways — a scenario the National Highway Traffic Safety Administration said raises the risk of crashes and injuries.
The recall affects vehicles equipped with Waymo’s 5th and 6th Generation Automated Driving Systems. The Mountain View, Calif.-based company reported the defect to NHTSA on May 1, 2026, and the agency acknowledged the recall in a letter dated May 11.
Under normal circumstances, a properly functioning autonomous driving system is expected to detect and avoid road hazards including flooded surfaces. In this case, according to NHTSA’s recall notice, the software did the opposite — it recognized the hazard enough to slow the vehicle but then allowed it to continue forward into the standing water anyway.
“Entering a flooded roadway can cause a loss of vehicle control, increasing the risk of a crash or injury,” the agency said in its official recall acknowledgment.
Waymo has already deployed an interim fix. According to NHTSA, the company imposed tighter weather-related restrictions and updated the maps used by the vehicles to navigate. The company said all 3,791 affected vehicles received that interim software update by April 20, 2026, before the recall was formally filed with the agency.
Waymo has not yet provided a permanent fix, which the NHTSA flagged in its letter to the company. Waymo will need to provide a full description of the final recall remedy as required under federal regulations. Waymo is also required under federal law to submit eight consecutive quarterly status reports on the recall, followed by three annual reports — a process that could span several years as the company works toward a complete fix.
The recall is the latest regulatory scrutiny facing the autonomous vehicle industry as companies push to expand driverless services into more cities and conditions. Waymo currently operates commercial robotaxi services in several U.S. markets including San Francisco, Los Angeles and Phoenix.