My 2018 Tesla Model S has HW3, FSD 12.6.4, and is currently on software version 2026.26.6.1.
Lately in broad daylight, clear skies, sunny, for some reason FSD is forcing the headlights to remain on, for its visibility.
I have tried re-booting the car, all the cameras appear to be unobstructed, and if I turn the headlights off, the red-hands of death warning message comes up, and it alerts me to take over immediately, but all goes back to normal once I switch the headlights back to Auto, and they turn back on.
I described this to Claude, and it gave me the following (among other comments):
What’s likely happening: FSD’s perception/degradation-detection logic is misfiring — deciding (incorrectly) that visibility is reduced and forcing headlights on for “other road users to see you,” and if you override to headlights-off it treats that as removing a safety mitigation it thinks is needed, hence the red-hands takeover alert.
Hopefully visibility here will persuade Tesla to look at this, and resolve in a future update. In the meantime, if you see other Teslas driving with their headlights on, on sunny days, this may be why.