Lexus SC300 front and rear side marker bulbs utilize 194 and 168 sizes respectively. The replacement chart covers 1992 to 2000 model production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Lexus SC300 uses the 194 bulb for the front side marker position across the full 1992-2000 model year range covered by these specifications.
The rear side marker position on the SC300 uses the 168 bulb across the same 1992-2000 model year range.
Both the 194 and 168 are ANSI-standardized bulb types recognized in the United States and Canada, meaning they conform to a defined set of electrical and physical characteristics.
Both bulbs share the T10 miniature wedge form factor, which refers to a small, wedge-shaped base that seats directly into a socket without a separate metal base or pins.
Both bulbs operate on a 12-volt system, consistent with standard automotive electrical architecture.
Although the 194 and 168 share the same T10 wedge form factor and voltage rating, they are not interchangeable. The 194 is rated at 3.78 watts while the 168 is rated at 4.9 watts, reflecting a difference in filament resistance and current draw.
Installing a 194 in a socket specified for a 168 would result in lower light output than intended, since the 194 draws less power and produces less luminous intensity.
The wattage difference between the two bulbs means that substituting a 168 into a front side marker socket designed for a 194 would draw more current than the circuit was designed to handle, which can stress the socket and wiring over time.