[nawgz]

I would find it hard to believe that the failure mode of these headlights wouldn't be "points straight and doesn't auto-dim ever", which reduces it to the previous implementation's graceful aging modes, but you are right a new possibility is introduced.

[idiotsecant]

I would absolutely believe the failure mode will be that one headlight will stop moving when it's commanded to, which best case means straight headlight, worst case means aimed where it shouldn't be 99% of the time