The Isuzu Axiom brake light requires a 7443 bulb size for proper installation and function within the rear lighting assembly. Data for the specified component covers the range from 2002 to 2004.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Isuzu Axiom uses the 7443 bulb for its brake lights across the 2002-2004 model years.
The 7443 is an ANSI-standard dual-filament wedge bulb in the T20 form factor, rated at 12V with a 21W/5W output, where the higher wattage filament serves the brake function and the lower wattage filament serves a secondary function such as running lights.
The dual-filament design of the 7443 means it cannot be directly substituted with a single-filament bulb without losing one of its two lighting functions.
The center high mount stop light on the Axiom uses the 921 bulb across the 2002-2004 model years.
The 921 is an ANSI-standard single-filament wedge bulb in the T15 form factor, rated at 12V and 16W.
The T15 form factor of the 921 is physically smaller than the T20 form factor of the 7443, making the two bulbs non-interchangeable despite both using wedge-style bases.
Both the 7443 and 921 carry ANSI designations valid in the US and Canada, indicating standardized electrical and physical specifications recognized across North American automotive applications.