A will has no effect until it is submitted to the court for probate. If there is no need to probate the will, then there is no need for notice.
However, in CA, the person petitioning the court to be appointed as the estate's personal representative is supposed to send notice of the hearing on the petition to the heirs and those named as devisees in the will.
Many CA counties have some probate information online. Find the website of county where the deceased resided. If the information is not online, call the court.