Update, August 18, 2026: Waymo published a post-outage note three days later and said it was changing how the fleet treats dark signals. Tesla still did not run unsupervised commercial robotaxis on San Francisco streets in December 2025. A supervised FSD clip and a paused Waymo fleet are different products.
On December 20, 2025, a PG&E substation fire blacked out a large part of San Francisco. Traffic lights went dark. BBC, The Guardian, and ABC7 showed Waymo robotaxis sitting in intersections with hazards on. Waymo paused service that Saturday. Tesla’s @Tesla_AI account posted a Model Y clip on Full Self-Driving (Supervised). Elon Musk wrote: “Tesla Robotaxis were unaffected by the SF power outage.”
The video shows a Tesla with a driver still responsible. It does not show Tesla beating Waymo at driverless taxi service in San Francisco. Tesery’s same-day Waymo blackout report covers the stranded Jaguars. This note is about what Tesla actually posted — and what the comparison does not prove.
Key facts
- When: Saturday, December 20, 2025. A PG&E substation fire cut power to well over 100,000 customers in western San Francisco.
- What failed: Streetlights and traffic signals. City crews and police ran some intersections by hand.
- Waymo: Driverless taxis stalled on dark signals; the company paused SF service that night.
- Tesla: @Tesla_AI posted dashcam of a Model Y on FSD (Supervised). Musk called them “Robotaxis.”
- What was not shown: An unsupervised Tesla taxi fleet continuing paid rides in San Francisco.
Tesla Robotaxis were unaffected by the SF power outage
— Elon Musk (@elonmusk) December 21, 2025
What Waymo said happened
Waymo’s December 23 blog said the driver is trained to treat a dark signal as a four-way stop, and that the fleet still “traversed more than 7,000 dark signals” that Saturday. The problem, Waymo said, was a spike in confirmation checks when the whole city went dark at once — not that every car forgot how to move. CNBC reported the company then pushed a fleet update so cars would need fewer remote checks next time.
That is a real operational failure for a driverless taxi. Cars with no one in the front seat sat in live traffic. It is also narrower than “Waymo cannot drive in the dark.” The lights were out, the city was already gridlocked, and Waymo chose to pause rather than keep adding frozen vehicles.
What Tesla posted — and what “Robotaxi” meant that night
@Tesla_AI’s clip, credited to @edgecase411, shows FSD moving through unlit streets and dark signals. The caption was: “FSD is trained on billions of real-world miles, including power outages.” That is a supervised owner-car video. Tesla did not publish a San Francisco robotaxi dispatch log. In December 2025 Tesla’s paid driverless service was still a limited Austin/Bay-area experiment, not a citywide SF taxi replacement. See Tesery’s later Austin Robotaxi count.
A human can still take over a Tesla. A Waymo rider cannot grab a wheel. Comparing those two videos as if they are the same test is the mistake the original magazine copy made. Supervised FSD can look smooth in one clip and still leave the driver legally in charge. California later moved to let police ticket driverless cars; that fight is about robotaxis, not owner FSD. See Tesery’s California robotaxi-ticket law.
FAQ
Did Tesla Robotaxis keep running paid SF rides during the blackout?
Tesla did not show that. Musk used the word “Robotaxis.” The public evidence is a supervised FSD video of a Model Y.
Did every Waymo freeze?
No. Waymo said it crossed thousands of dark signals and paused because remote checks spiked and cars were blocking streets.
Does camera-only FSD beat lidar when the power dies?
This outage does not settle that. Dark signals are a software policy problem as much as a sensor problem. Waymo’s own write-up treats it that way.
For owners: FSD (Supervised) may keep moving when city lights fail. You are still the driver. Treat a dark signal as a four-way stop, same as the handbook.
Featured photo: San Francisco at night from Twin Peaks (file photo; lights are on — this is not a blackout picture). Image via Wikimedia Commons.
Related: Waymo taxis stalled in the same SF blackout · FSD v14.2.2.1, shipped the same week · Austin Robotaxi: citywide map, ~20 cars · California’s robotaxi-ticket law
.jpg){kind=link}