The Scion xA tail light requires a 7443 bulb size for proper installation and function within the rear lighting assembly. Data for the specified bulb covers the 2004 to 2006 range.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 7443 is the sole bulb type specified for the Scion xA across all listed model years and positions, making it the defining bulb for this application.
The 7443 follows the ANSI standard recognized in the United States and Canada, classifying it as a regionally standardized automotive bulb rather than a globally universal one.
This bulb belongs to the T20 wedge family, a form factor characterized by a plastic wedge base that seats directly into a socket without a separate metal base or bayonet pins.
The 7443 operates on a 12-volt circuit, consistent with the standard electrical architecture found in passenger vehicles of this type.
Its dual-filament design carries two distinct wattage ratings: 21W for the high-intensity filament and 5W for the low-intensity filament, allowing a single bulb to serve both braking and running light functions within one housing.
The outer tail light position on the Scion xA (2004-2006) uses the 7443 consistently across all three model years, indicating no mid-cycle bulb specification change occurred during that production span.
The dual-filament nature of the 7443 means it is not directly interchangeable with single-filament T20 variants such as the 7440, which shares the same base style but lacks the second filament required for combined stop and tail functions.