Scion xB front side marker bulbs utilize 168, 1034NA, or 1157NA bulb sizes, while rear side marker bulbs require 7443 bulb size. The replacement chart covers 2004 through 2015 vehicle production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 168 bulb is the front side marker fitment for the Scion xB across the 2008-2015 model years. It is an ANSI-standard miniature wedge bulb in the T10 form factor, rated at 12V and 4.9W, and is among the lower-wattage bulbs in these specifications.
The 7443 bulb covers the rear side marker position on the xB for the same 2008-2015 span. It is a dual-filament T20 wedge bulb rated at 12V with a 21W high filament and a 5W low filament, making it significantly more powerful than the 168 used at the front.
The 2004 and 2006 xB front side marker positions call for the 1034NA bulb, a dual-filament type with a BAY15d bayonet base and natural amber glass, rated at 12V and 21/5W. The bayonet base of the 1034NA is physically distinct from the wedge base of the 168, so the two bulb types are not interchangeable.
The 2005 xB front side marker uses the 1157NA, which shares the BAY15d bayonet base and natural amber glass construction with the 1034NA but is a separate ANSI designation. Both the 1034NA and 1157NA are variants within the 1157 family, though they carry different part numbers and should not be substituted without confirming the specific fitment year.
The natural amber glass on both the 1034NA and 1157NA produces a colored output directly from the bulb rather than relying on a tinted lens, a construction detail relevant when sourcing replacements, since a clear-glass substitute would alter the emitted color.
The front and rear side marker positions on the 2008-2015 xB use bulbs from two different base families: the T10 wedge (168) at the front and the T20 wedge (7443) at the rear. Despite both being wedge-base types, the T10 and T20 sockets are sized differently and the bulbs are not cross-compatible between positions.