Depends on the brand and car but mine for example automatically adjusts the speed to the detected sign. But you can always override it of course. It sometimes (not often but sometimes) detects 50km/h speed limit somewhere although there is 100km/h. Would be pretty dangerous if you wouldn’t be able to override that.
https://en.wikipedia.org/wiki/Traffic-sign_recognition
Depends on the brand and car but mine for example automatically adjusts the speed to the detected sign. But you can always override it of course. It sometimes (not often but sometimes) detects 50km/h speed limit somewhere although there is 100km/h. Would be pretty dangerous if you wouldn’t be able to override that.