The Acura RSX brake light utilizes a 7443 bulb size for the rear lighting system on the vehicle. Data for the specific component covers the period from 2002 through 2006.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Acura RSX uses the 7443 bulb for its brake lights across the full 2002-2006 model range.
The 7443 is a dual-filament T20 wedge bulb rated at 12V with a 21W/5W output, conforming to ANSI standards for the US and Canadian markets.
The dual-filament design of the 7443 allows it to serve two separate lighting functions within a single housing, with the higher 21W filament handling the brake light function and the lower 5W filament handling a secondary function such as a tail light.
The center high mount stop light on the Acura RSX uses the 7440 bulb across the full 2002-2006 model range.
The 7440 is a single-filament T20 wedge bulb rated at 12V, 21W, also conforming to ANSI standards for the US and Canadian markets.
Although the 7443 and 7440 share the same T20 wedge base and physical form factor, they are not interchangeable. Installing a 7440 in place of a 7443 would result in the loss of one lighting function due to the absence of a second filament.
The reverse relationship also presents a fitment concern, as a 7443 installed in a 7440 socket may not operate correctly depending on how the circuit is wired for a single-filament application.