What is the test for a defendant to request separate counsel in a personal injury action?

" 'If defendants were denied the right to effective representation of counsel, we cannot presume that the right was waived by a failure to request separate counsel. The court did not advise them of their right to separate counsel if a conflict was present, and we cannot imply from their silence a waiver of that right. (Citations.)' (People v. Chacon, supra, 69 Cal.2d at p. 774, (73 Cal.Rptr. 10, 447 P.2d 106).)

"It is further the rule that if the codefendants have not been informed of their right to separate counsel in the event of a potential conflict of interest between them, and if the record later indicates that there was an actual conflict of interest, the matter of separate counsel may be reviewed on appeal. 'And, significantly, the appellate court may use hindsight to ascertain whether or not there was an actual conflict of interest and, if so, whether appellant was injured (People v. George, 259 Cal.App.2d 424, 432, (66 Cal.Rptr. 442) . . . .)' (People v. Mitchell (1969) 1 Cal.App.3d 35, 38, (81 Cal.Rptr. 478) . . . ; fn. omitted.)" (Id., at pp. 518-519, 148 Cal.Rptr. at pp. 519-520.)