Waymo suspends service in San Francisco as robotaxis stall during blackout
62 comments
·December 21, 2025MBCook
kylehotchkiss
I would just push them all out of the way with my fire truck, I mean one fire truck could probably clear 6-8 Waymos at a time, right?
malfist
Fire trucks are very expensive to be playing bumper cars with
JumpCrisscross
> Come the next Big One earthquake, all of San Francisco’s emergency services will be blocked by Waymos
Were any emergency vehicles actually blocked?
We have an actual failure here–step one is identifying actual failures so we can distinguish what really happened from what hypothetically could.
MBCook
I don’t know. But if human drivers are having to go around them, they’re not doing the right thing.
They need to drive or pull over. Never just stop there in the road and wait.
JumpCrisscross
> if human drivers are having to go around them, they’re not doing the right thing
They're not. But it's also not a disaster. Pretending it is on Twitter is pandering, not policymaking.
> They need to drive or pull over. Never just stop there in the road and wait
Agreed. Waymo has a lesson to learn from. Sacramento, and the NHTSA, similarly, need to draw up emergency minimums for self-driving cars.
There are productive responses to this episode. None of them involve flipping out on X.
SoftTalker
A fire truck can simply push the waymo out of the way.
justin66
It can’t push a block of gridlocked traffic that cannot move because of the dead waymos present out of the way.
MBCook
It can do that with a normal driver too. Doesn’t make it ok for there to ever be a situation where they need to when the target vehicle/driver is just fine and capable of doing it themselves.
JumpCrisscross
> A fire truck can simply push the waymo out of the way
Sure, but it would be notable if one had to. If none had to, we have a problem to solve, not a catastrophe.
andsoitis
Seems like a power outage is a an obvious use case Waymo should have foreseen.
Makes me think there are likely other obvious use cases they haven’t thought about proactively either.
JumpCrisscross
> Seems like a power outage is a an obvious use case Waymo should have foreseen
We have zero evidence a power outage wasn't foreseen. This looks like a more complex multi-system failure.
MBCook
Does it matter?
Once you’re on public roads, you need to ALWAYS fail-safe. And that means not blocking the road/intersections when something unexpected happens.
If you can physically get out of the way, you need to. Period.
JumpCrisscross
> Does it matter
Yes. OP is inferring Waymo's internal processes from this meltdown. ("Makes me think there are likely other obvious use cases they haven’t thought about proactively either.")
If Waymo literally didn't foresee a blackout, that's a systemic problem. If, on the other hand, there was some weird power and cellular meltdown that coïncided with something else, that's a fixable edge case.
pjc50
It also means that their claims of "autonomy" are fraudulent, like most "self driving" cars. A car which depends on powered infrastructure outside the car to drive is not autonomous.
bigyabai
Nearly all humans depend on powered infrastructure outside their car to drive it. You're describing a shortcoming of all 21st century navigation.
basilgohar
I think the 100 or so miles I can generally drive in my car while it still has gas is different from my car just stopping suddenly because of a power outage.
AyyEye
Tell that to all of the humans who were capable of driving, but blocked by a fake autonomous car that froze in the middle of the road.
null
BlackjackCF
Yeah, I was shocked by this. Blackouts in California aren’t some sort of rare event. I’m primed to expect rolling brownouts/blackouts yearly in the summer.
duhast2020
There haven't been rolling blackouts since 2001.
Wowfunhappy
Neither a lack of traffic lights nor cell service should cause the Waymos to stop in the middle of the road, that’s really troubling. I can understand the system deciding to pull over at the first safe opportunity, but outright stopping is ridiculous.
HarHarVeryFunny
Waymos rely on remote operators to take over when the vehicle doesn't know what to do, and obviously if the remote connection is gone then this is no longer available, and one might speculate that the cars then "fail safe" by not proceeding if they are in a situation where remote help is called for and inaccessible.
Perhaps traffic lights being out is what caused the cars to stop operating autonomously and try to phone home for help, or perhaps losing the connection home is itself enough to trigger a fail safe shutdown mode ?
It reminds a bit of the recent TeslaBot video, another of their teleoperated stunts, where we see the bot appearing to remove a headset with both hands that it wasn't wearing (but that it's remote operator was), then fall over backwards "dead" as the remote operator evidentially clocked off his shift or went for a bathroom break.
MBCook
That’s clearly unacceptable. It needs to gracefully handle not having that fallback. That is an incredibly obvious possible failure.
Things go wrong -> get human help
Human not available -> just block the road???
How is there not a very basic “pull over and wait” final fallback.
I can get stating out if the car thinks it hit someone or ran over something. But in a situation like this where the problem is fully external it should fall back to “park myself” mode.
JumpCrisscross
> How is there not a very basic “pull over and wait” final fallback
Barring everything else, the proper failsafe for any vehicle should be to stop moving and tell the humans inside to evacuate. This is true for autonomous vehicles as well as manned ones–if you can't figure out how to pull over during a disaster, ditching is absolutely a valid move.
gnabgib
Discussion (87 points, 14 hours ago, 85 comments) https://news.ycombinator.com/item?id=46342412
alistairSH
Anybody on the ground confirm if it was the traffic lights or lack of cellular that cussed the stoppages?
isodev
I think it’s clear that both use cases are a must have during an emergency. Even more, rescue services and stranded people would need all the bandwidth and reception they can get, Waymos shouldn’t be online during such times at all.
jerlam
First responders get the highest priority of cellular networks even in non-emergency situations (FirstNet).
AlotOfReading
FirstNet is AT&T. Verizon and T-Mobile have their own alternatives (FrontLine and T-Priority, respectively). QCI is a fun rabbit hole, because some of these networks share the first responder QCIs with certain business use cases.
nerdsniper
I didn’t notice a lack of cellular. Though it did get down to like 6Mbps, which was certainly degraded service.
torham
I lost cell during the whole outage on Verizon, came back immediately when power was restored. There seemed to be some towers up, if i walked down the street I could find one, but plenty were down.
kylehotchkiss
Did anybody get stranded on the bart?
bink
It was predicted by many, including me. It'll be a lot worse in an earthquake where power and cell service are out and there's debris and road damage. Good luck to our first responders.
tiahura
How does Tesla FSD respond to inactive traffic control lights?
tanvach
Coincidentally we were on the Robotaxi during the black out (didn’t know about it, we were going to Japan town from the Mission). Noticed that it navigated through the non-working traffic lights fine, treated it like a stop sign junction. One advantage of building unsupervised system from public version that had to deal with these edge cases all around the country.
Though the safety driver disengaged twice to let emergency vehicles pass safely.
andsoitis
Treats it as a four way stop.
https://www.tesla.com/ownersmanual/modely/en_eu/GUID-A701F7D...
jerlam
That manual entry does not exude confidence.
It might work, if other Tesla drivers regularly drive in that area. Also, it might not work, and you should assume that it won't work.
GMoromisato
https://x.com/edgecase411/status/2002630953844552094
Looks like it treats it as a 4-way stop. Is this because Tesla has more training data?
gertlex
I'd default to assuming it's the respective roadmaps for Waymo and Tesla differed on which things to implement when, not training data, that results in the two behaving different.
brianwawok
50/50 bet it would either go right through or treat it as a stop.
Don’t think I have had a totally inactive light. I have had the power is out but emergency battery turned to blinking red light, and it correctly treats as a stop sign.
EA-3167
I think Tesla doesn’t care a out their reputation like Waymo does.
JumpCrisscross
> Is this because Tesla has more training data?
Its human takes over. FSD is still Level 3.
(Robotaxi, Tesla's Level 4 product, is still in beta. Based on reports, its humans had to intervene.)
AlotOfReading
FSD is level 2. Level 3 doesn't require the human driver to monitor the outside environment, only take over when requested. Tesla also doesn't report data from FSD under L3 reporting requirements anywhere in the US.
cess11
I think I prefer trains and buses.
chroma
SF Muni & BART both stopped service in many areas. Though most of the trains still had electricity, many sensors and control systems were inoperable. Also underground stations had no lighting, so it would be hazardous to allow people to board or exit there.
Waymo's problem is obvious in hindsight, and quite embarrassing for them, but it can be solved with software improvements. Tesla's FSD already treats dark traffic lights as stop signs, so I would bet on Waymo fixing this as soon as they can.
But transportation that depends on infrastructure along the whole route (such as trains and busses powered by overhead lines) are always going to fail in these situations. I think that's acceptable considering how rare these events are.
laweijfmvo
So basically no answer from Waymo other than to boast about their numbers? Why not just be transparent?
jerlam
The "boast about numbers" wasn't from Waymo, it was from their investors, and it was earlier this month and not during the service suspension.
krisoft
What do you mean no answer? They are suspending their operations. That is their answer.
NetMageSCW
Read more carefully, Waymo didn’t boast about their numbers and that part of the story was unrelated to the issue except as a measure of impact their shutdown could have.
nextworddev
Because they are currently trying to raise money at 100bn valuation
SoftTalker
"San Francisco Mayor Daniel Lurie warned residents to stay off the roads unless they needed to travel."
Sure, I go out and drive around on the roads for no reason all the time. I'll avoid doing that during the crisis.
nerdsniper
I did when I was younger (18-25). Exploring the world outside of my hometown often put me at ease when I was feeling destabilized.
casion
Unsure if sarcasm, but lots of people do that. I do it every day.
Some folks enjoy driving.
SoftTalker
Yeah it was sarcasm. I enjoy driving also, actually. But I don't just go out and drive for no reason. It's always with a purposeful destination.
From John Ripley on Mastodon:
“Thought of the day, and I wish there were a way to get this to legislators:
Come the next Big One earthquake, all of San Francisco’s emergency services will be blocked by Waymos.”
I’m AMAZED they’re not designed to handle this better. This does indeed seem like a massive problem. “Oops we give up” right when things get the worst? How is this OK?
I’ve been very impressed by Waymo’s more cautious approach. Perhaps they haven’t fully thought through the ramifications of it though.
https://mastodon.social/@jripley/115758725115731454