Why Waymo’s Self-Driving Cars Shut Down in San Francisco
When the lights didn't glow, Waymo was no go in San Francisco
So what happened? Why did the Waymos go No Go?
That was the question in San Francisco over the weekend.
A major power outage knocked out electricity to tens of thousands of homes. It also knocked something else off balance — the Waymos.
As traffic lights went dark, self-driving Waymo cars rolled up to intersections and then just… stopped. Hazard lights blinking. Cars piling up behind them. Human drivers getting angry. Tow trucks getting busy.
Tow operators said they were hauling Waymos for hours overnight. Social media filled up with videos of stalled cars sitting in the middle of intersections, looking confused, or at least as confused as a car can look.
Waymo temporarily shut down its ride-hailing service across the Bay Area. The company says service has since resumed.
Waymo — owned by Alphabet, which also owns Google — launched in San Francisco in 2023. There are now about one thousand of the cars roaming city streets. They’ve become a kind of moving curiosity. Tourists film them. Some riders love them. Some women say they feel safer in a driverless car. Some parents even use them for school pickup.
So — again — what happened?
At first, people assumed the outage somehow cut the cars off from central control. That sounded reasonable. It was also wrong.
Waymos are designed to keep driving even if they lose wireless connections. They’re built to handle dead traffic signals, too. San Francisco loses traffic lights all the time, especially during bad weather. Normally, that doesn’t faze the cars.
They run on onboard batteries. They can drive through areas with no signal. And when they hit something they can’t figure out, remote technicians can step in and help.
But this time, the outage was everywhere.
Waymo says its cars are programmed to treat dark signals as four-way stops. The problem, according to the company, was scale. So many intersections went dark at once that the cars became overly cautious, waiting longer than usual to confirm what was going on. That hesitation stacked up. Traffic backed up. Frustration followed.
No injuries were reported, according to city officials.
Waymo has had issues before. The company has issued recalls after software problems led to collisions — including one with a pickup truck and another with a telephone pole in Phoenix.
Still, not everyone was upset.
The New York Times spoke with Eric Black, who saw nearly a dozen stalled Waymos while driving to the Richmond District. He said he was relieved they stopped instead of pushing through a dangerous situation.
He also noticed something else.
Most of the close calls he saw that day involved human drivers — not the robots.
Which may be the quiet lesson here: when the world goes dark and confusing, the machines chose to freeze. The people did not.
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I agree with Eric Black. Autonomous cars, like everything else, will need some tweaking to make them perfect. No amount of tweaking will get people to drive with prescribed uniformity, to say nothing of making them pay attention—technology rocks.