What is the test for imposing a proper sentence on a defendant who has been found guilty of gross negligence under the California Penal Code?

" ' "It is well established that when the trial court pronounces a sentence which is unauthorized by the Penal Code that sentence must be vacated and a proper sentence imposed whenever the mistake is appropriately brought to the attention of the trial court or the reviewing court." This rule also applies to sentences which are unauthorized because of an error in the matter of restitution.' " (People v. Zito (1992) 8 Cal.App.4th 736, 741-742 [imposition of direct victim restitution and restitution fine that exceeded pre-1990 statutory maximum].)