If you're interested in the "actual" fix, we'll need the code(s) that's thrown. The electrical schema shows that If any component in the driving safety systems fail, cruise will be disconnected.

 

This happens when battery is not fully charged or because it’s used and not possible to get 100% of charge.
The system cannot check correctly the whole car because of the lack of power… then faulty message appears.
I have replaced the battery ; it’s fully operational now.