Scion xA high beam and low beam headlight bulbs both use a 9003 size. The replacement chart covers 2004 through 2006 model years with bulb specifications for each production year.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 9003 is the sole bulb type listed across all headlight positions for the Scion xA, covering both high beam and low beam functions for the 2004-2006 model years.
The 9003 is a dual-filament halogen bulb, meaning a single bulb contains two separate filaments: one rated at 60 watts for high beam output and one rated at 55 watts for low beam output.
Because the 9003 serves both the high beam and low beam positions in the Scion xA, the vehicle uses the same physical bulb in each headlight housing to perform both lighting functions.
The 9003 operates on a 12-volt electrical system, which is standard for passenger vehicles, and draws different wattage depending on which filament is active at a given time.
The 9003 uses a P43t base, a standardized bayonet-style fitting that determines physical compatibility with a headlight housing socket.
The 9003 designation follows ANSI standards applicable in the United States and Canada, distinguishing it from the functionally similar H4 bulb used in other markets, which shares the same dual-filament design but uses a different base type and is not directly interchangeable.