The Lexus GS430 brake light requires a 7443 bulb size for proper installation and function within the rear lighting assembly. Data for the specified vehicle covers the range from 2001 through 2004.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Lexus GS430 uses the 7443 bulb across the brake lighting system for the 2001-2005 model years, covering the inner brake and outer brake positions throughout that entire span.
The 7443 is a dual-filament T20 wedge bulb rated at 12V with a 21W/5W output, meaning its two filaments serve different brightness levels, which suits combined stop and tail light functions within a single housing.
The center high mount stop light on the 2005 GS430 uses a 194 bulb, while the 2001-2004 model years use a 168 bulb in that same position.
Both the 194 and 168 are T10 miniature wedge bulbs operating at 12V, but they differ in wattage. The 194 is rated at 3.78W and the 168 at 4.9W, making them electrically distinct despite sharing the same physical wedge base form.
Because the 194 and 168 share the T10 wedge base, they may physically fit the same socket, but their differing wattage ratings mean they are not confirmed interchangeable for the GS430 center high mount stop light without verifying the correct year.
All bulb sizes listed for the GS430 conform to ANSI standards applicable in the United States and Canada.
The 7443 bulb is not interchangeable with the 194 or 168 bulbs, as it belongs to the T20 wedge family rather than the T10 family, and operates at a substantially higher wattage.