{"code":"VEH","codeName":"Vehicle Code","section":"521","citation":"Veh. Code, § 521","status":"in-force","lawOn":"2026-09-28","headings":[{"name":"DIVISION 1. WORDS AND PHRASES DEFINED [100. - 681.]","url":"https://blackletter.si/vehicle-code/division-1"}],"history":"Added by Stats. 1991, Ch. 648, Sec. 1.","effective":null,"html":"<p>A “retarder” is a device, other than a brake, which, when activated by the driver, applies a retarding force to the wheels of a vehicle without the use of friction. A retarder may be installed in or on the engine, exhaust system, drive train, or wheels of a motor vehicle, or an axle or wheels of a towed vehicle. A retarder may operate by altering the valve timing of the engine, by controlling the flow of a circulating fluid, by applying an electromagnetic force, by controlling the release of gases from the exhaust system, or by other means. A retarder may or may not be capable of stopping the vehicle upon which it is installed.</p>","text":"A “retarder” is a device, other than a brake, which, when activated by the driver, applies a retarding force to the wheels of a vehicle without the use of friction. A retarder may be installed in or on the engine, exhaust system, drive train, or wheels of a motor vehicle, or an axle or wheels of a towed vehicle. A retarder may operate by altering the valve timing of the engine, by controlling the flow of a circulating fluid, by applying an electromagnetic force, by controlling the release of gases from the exhaust system, or by other means. A retarder may or may not be capable of stopping the vehicle upon which it is installed.","otherVersions":[],"url":"https://blackletter.si/vehicle-code/words-and-phrases-defined-521","source":"California Legislative Information bulk export (pubinfo)"}