California Code, Vehicle Code - VEH § 22501

No ordinance enacted by local authorities pursuant to subdivisions (e) and (k) of Section 22500 or Section 22507.2 shall become effective as to any state highway without prior submission to and approval by the Department of Transportation in the same manner as required by Section 21104.  Nothing contained in this section and Section 22500 shall be construed as authorizing local authorities to enact legislation which is contrary to the provisions of Sections 22512 and 25301.