How does the "hands on wheel" warning really work?

[Erik The Red]

So lately, i've been frustrated by my Model S on FSD beta alerting me to put my hands on the wheel. That would be understandable, if my hands weren't already on the wheel. And yes, i have slight torque applied.

However, this seems to happen all of a sudden, with no warning, the red alert with beeping occurs without any the silent flash/warnings occurring. I'm just going along and WHAM beep beep beep, sometimes even going right to the red steering wheel warning, bypassing the passive and even first level red warnings, literally giving me a second or two to apply more torque to avoid a forced disable.

So I have a theory, and I'm curious if anyone else feels the same. I think many of assume there are several "stages" before forced disable. You must go through each stage one after the other and finally it shuts you out. I think that's wrong.

Instead, I think each type of alert (silent, red, red wheel, disable) has it's own timer and its own torque measurement. each stage has a progressively longer timer. So, let's say stage 1 is 5 seconds, 2 is 10 seconds, 3 is 15 seconds, disconnect after 20. Ok, but what can happen is you are applying enough torque to satisfy stages 1, 2, and 3, but not stage 4... so it silently jumps directly to disconnect after 20 seconds because you were just at the cutoff torque, failing to give you any warning whatsoever.

Anyone else feel like this is the case?

 

[RTPEV]

I suspect this is not a "making sure you are paying attention" alert, but rather the car sees something it doesn't feel like it can handle and wants you to take over immediately. In that case, no, you need to take over immediately or the car may do something stupid!

 

[diplomat33]

However, this seems to happen all of a sudden, with no warning, the red alert with beeping occurs without any the silent flash/warnings occurring. I'm just going along and WHAM beep beep beep, sometimes even going right to the red steering wheel warning, bypassing the passive and even first level red warnings, literally giving me a second or two to apply more torque to avoid a forced disable.

The sudden, out of the blue, "red hands on wheel" warning happens when AP/FSD detects something that causes it to lose confidence. It is not about lack of torque AFAIK.

 

[NCC81701]

I'm pretty some of those red hands on wheels warning, especially during an intersection, is when FSD isn't sure about something as it cross the intersection and wants to make sure you have hands on wheel in case it does run into trouble. I've seen these warnings generally during a "complex" intersection, camera being possibly partially obscured/blind by the sun, or a combination of both. I seem to recall that no torque was necessary once the car was through the problematic area and continues to drive on FSD.

I kinda expect this kind of stuff for a testing environment and is why I wouldn't just hand someone my car w/ FSD and tell them to just try it out. it's a good warning to have, but it would totally freak someone out if they aren't use to using FSD day in and day out.

 

[medphys3]

The above two explanations seem reasonable. My car always yells at me when I enter a construction zone with orange barrels even though I haven't been nagged for the previous 20 miles.

 

[Dewg]

The sudden, out of the blue, "red hands on wheel" warning happens when AP/FSD detects something that causes it to lose confidence. It is not about lack of torque AFAIK.

It also happens when the AP/TACC/FSD Beta stack fails - think of it like a Sad Mac, or Windows Blue Screen of Death. The NNs and controlling software (referred to as the stack) crashes. Then the main drive ECU detects the crash and gives you the red wheel and loud beeps to take over - you will likely also see a "Cruise Control is Not Available" warning at the bottom of the screen. You may also notice the graphics get stuck, like the lanes are moving, but it's no longer showing surrounding cars, or it may show cars, but they are all frozen in place. The stack is rebooting at this point, and it takes about 30-60 seconds for the software to restart. Once it restarts, you'll see a quick flash on the screen (might not even notice it), and then the visualizations will all start working again. You can then re-activate AP/TACC/FSD Beta.

This is actually a good thing that Tesla has modularized their FSD solutions. It means you can keep driving, even though a feature crashed and is restarting. I would hate it if you got the red-wheel error and then nothing worked until you pulled over and rebooted the entire car.

 

[Erik The Red]

Yes, i've seen the warnings when it sees traffic cones or other issues, and those make sense. But i've encountered a number of these even in clear conditions.. my hand resting heavily on the wheel to provide torque. It sometimes needs additional torque... not sure if this is some kind of measure to prevent bypass devices, but the key issue is that it skips the silent white flash warning.

 

[diplomat33]

Yes, i've seen the warnings when it sees traffic cones or other issues, and those make sense. But i've encountered a number of these even in clear conditions.

Just because the conditions look clear to you does not mean that it is necessarily clear to AP/FSD. There could still be something that is confusing AP/FSD that you don't know about. Camera vision can be fickle sometimes. Or the software had a glitch. I used to sometimes have the AP2 computer crash on me for no apparent reason, driving on a clear day. In any case, the fact that you were applying enough torque suggests that the issue is not a lack of torque. You got the warning because the software ran into some sort of problem.

 

[Erik The Red]

Fair enough, especially in the FSD beta.

I've also noticed they fixed the workaround to preventing uploading data by doing a hard reset when a forced disable occurs. With the FSD Beta, if you get 3 forced disables in a month (i think) they drop you out of the beta. It used to be, you could stop (not putting it in park) and do a forced reset by holding down the buttons on the steering wheel, and it would never upload. Now, it knows you were bad even after a reboot.

 

[Twiglett]

sometimes it shows up in odd ways. I ended up driving a road that I always got those "red hand take over immediately" alarms.
This time I had my wife checking the display - for me it was AP/FSD beta mistaking tar lines on the road as a pedestrian, the display briefly showed a pedestrian before alerting and trying to slow down.
I reported it and could reproduce it. As I drive that road every week for the next month or so I'm reporting twice a week now

 

[tm3caruppan]

I suspect this is not a "making sure you are paying attention" alert, but rather the car sees something it doesn't feel like it can handle and wants you to take over immediately. In that case, no, you need to take over immediately or the car may do something stupid!

First of all, I don't know what it is thinking. Secondly I don't see any dangerous situation myself with my own eyes. Still if it feels it needs my attention, it can ask for it. But it has no business disabling the FSD altogether "until the next software update" right away. That doesn't make sense at all. It is as if, my driver, who I paid in advance, is punishing me for not driving and takes my money and runs.

 

[RTPEV]

First of all, I don't know what it is thinking. Secondly I don't see any dangerous situation myself with my own eyes. Still if it feels it needs my attention, it can ask for it. But it has no business disabling the FSD altogether "until the next software update" right away. That doesn't make sense at all. It is as if, my driver, who I paid in advance, is punishing me for not driving and takes my money and runs.

You may not know what it's thinking, but you can infer from the behavior (going immediately to full-on red alert) that that's what happened.

And yes, if the car (or driver) feels like they are approaching something it cannot handle, or your driver suddenly lost their vision for some bizarre reason, it's probably best to request you take over immediately rather than crashing into something, even if it turns out to be a false alarm.

And the OP didn't mention disabling FSD until the next software update, but rather simply disabling (deactivating) FSD/autopilot, which is what happens in those "take over immediately" situations.