If it's anything like the speed limit warning system in my Volvo, it's utterly useless. It gets the speed limit right about 80% of the time I would say. The other 20% it sees a sign "max 5 ton allowed" and thinks it means "max 5 kph", or it sees a sign in a side street and thinks it applies on the main street. Or a speed limit ends at a crossroad, which the system doesn't understand. The system often thinks the speed limit is 30 kph where it's actually 50 kph which is annoying; sometimes it thinks the limit is 90 or even 120 where it's only 50 or 70 which is outright dangerous.
The system is not to be trusted at all. There suggestions to make laws that would require cars to enforce these limits, instead of just showing the limits and warnings. I'm not against that in principle, but those systems need to get a lot better than the one in my Volvo first.