Waymo Issues Software Update After Robotaxis Stalled During Power Outage

Waymo rolled out a software update after several of its robotaxis stalled at intersections during a recent power outage in San Francisco. The incident drew attention to how autonomous vehicles handle rare, disruptive failures in city infrastructure.

What happened

A widespread power outage knocked out traffic signals across parts of San Francisco, leaving multiple intersections without working lights. Videos posted online showed Waymo robotaxis stopped at dark intersections with hazard lights on, and some areas saw localized congestion.

Waymo paused robotaxi service in affected areas during the outage. The company resumed Bay Area ride-hailing the next day after power and signals stabilized.

Why the vehicles stopped

Waymo says its system treats dark traffic lights as four-way stops. During the outage, unusual conditions triggered extra “confirmation checks” for some vehicles through Waymo’s fleet response process.

The outage created a surge in these requests, and the fleet response team faced a backlog. Some robotaxis waited longer than normal while the system requested and received confirmations.

What still worked

Waymo says its vehicles successfully traversed more than 7,000 dark signals during the outage. Only a subset of vehicles saw delays tied to the spike in confirmation requests.

The company says its safety behavior stayed consistent, with vehicles choosing caution when conditions fell outside typical patterns.

What’s changing

Waymo says it is deploying a fleet-wide software update that adds more context about regional power outages. The change aims to help vehicles handle dark signals more decisively and reduce unnecessary confirmation checks.

Waymo also says it will update emergency response protocols based on lessons from the outage. The company wants to cut response backlogs during similar events.

Regulatory attention

California regulators reviewed the incident involving stalled vehicles. The episode adds scrutiny to how robotaxi operators manage edge cases that affect public roads and traffic flow.

Why it matters

Robotaxi services run into new stress tests when city infrastructure fails at scale. The outage showed how software decisions and fleet operations can shape reliability during rare events, and Waymo’s update signals a push to make those scenarios smoother.