California Code, Health and Safety Code - HSC § 43202

No new motor vehicle required to meet the emission standards adopted by the state board pursuant to Section 43101 shall be sold and registered in this state unless the manufacturer thereof permits the state board to conduct surveillance testing of emissions of new motor vehicles at his assembly facilities, or at any other location where the manufacturer's assembly line testing is performed and assembly line testing records are kept.

Authorization for the sale and registration of any new motor vehicle in this state may be rescinded or withheld if, at any time, the state board is prevented by the manufacturer from conducting surveillance of assembly line testing.