The robotaxis service was suspended for hours as vehicles struggled to read malfunctioning stoplights amid a city-wide power outage.
A power outage that left 130,000 homes without electricity across San Francisco also forced the robotaxi operator Waymo to suspend services, as the driverless vehicles found themselves stuck at darkened traffic lights.
Videos posted on social media showed the Waymo cars blocked at intersections, as the vehicles were seemingly confused about how to proceed with a lack of traffic signals.
According to media reports, the Alphabet-owned company suspended services across the city on Saturday after being contacted by the San Francisco mayor’s office about the gridlock its vehicles were causing. Service resumed on Sunday afternoon.
The company, which introduced its driverless ride-hailing service in San Francisco in 2023, owns and operates some 1,000 vehicles across the city. Waymo said it plans to expand its services to Europe next year, starting with London.
Waymo vehicles are designed with onboard batteries that allow the cars to continue operating when they lose access to wireless networks or encounter traffic lights that have lost power.
The company said the scale of the blackout over the weekend caused the robotaxis to idle longer than normal at intersections as they assessed the situation.
Waymo told TechCrunch in a statement that the company is “focused on rapidly integrating the lessons learned from this event, and are committed to earning and maintaining the trust of the communities we serve every day.”
No accidents or injuries caused by the Waymo outage were reported, according to city officials.
The local energy provider, Pacific Gas and Electric Co. (PG&E), said the power outage was caused by a fire in one of its power stations in the city. The blackout left the city of 800,000 people in the dark for hours on Saturday, with one-third of customers affected at its peak.
The San Francisco Department of Emergency Management said on X that “significant transit disruptions” occurred citywide, and urged residents to avoid nonessential travel.
Power was restored to the majority of the city by Sunday, with full service expected to resume on Monday, according to a statement from PG&E.
