You will need to make sure of something very important... Be certain your Scion XB is 50-State Emissions Certified (California), as opposed to 49-State Emissions Certified (Federal). If it is only 49-State emissions legal, you will not be able to register it in California until it is considered a USED vehicle; when it has at least 7500 miles on the odometer. If your Scion is 50-State Emissions Legal, meaning it is California Emissions Certified, you may get it registered here. To find out which emissions certification it has, check the underhood emissions label. It should indicate 50-State Emissions Certified (California).