Yes. To prevent a vehicle registration suspension, you must notify DMV before you cancel your insurance. If you are not operating your currently registered vehicle, and it is not parked on a California roadway, you may submit an Affidavit of Non-Use (ANU) (REG 5090) to DMV.
After filing the ANU, the vehicle’s insurance may be cancelled. However, if the vehicle is still not in use when registration renewal fees are due, you must pay renewal fees or request the vehicle be placed on planned non-operation (PNO) status. You are not eligible to file an ANU once the registration expires.