Lexus IS250 front and rear turn signal bulbs utilize 7440NA and 7440 sizes respectively, with the front bulb featuring a distinct variant designation. The replacement chart covers 2006 through 2009 model years and documents bulb size specifications for turn signal applications across this production range.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Lexus IS250 uses the T20 wedge bulb platform for both front and rear turn signals across the 2006-2009 model years.
The T20 wedge base is a single-filament design, meaning each bulb serves one lighting function rather than combining two functions in a single housing.
Front turn signals on the 2006-2009 IS250 take the 7440NA bulb, which is a T20 wedge type with natural amber-tinted glass, rated at 12V and 21W.
Rear turn signals on the 2006-2009 IS250 take the 7440 bulb, which shares the same T20 wedge base, voltage, and wattage as the 7440NA but lacks the amber glass coating.
The natural amber glass of the 7440NA produces its amber signal color through the glass itself rather than through a colored lens or housing, which is the defining distinction between it and the standard 7440.
Both the 7440NA and 7440 are ANSI-standardized bulbs recognized in the United States and Canada, indicating conformance to a defined set of electrical and physical specifications.
Although the 7440NA and 7440 share the same T20 wedge base and electrical ratings, they are not interchangeable without consequence. Installing a 7440 in place of a 7440NA in the front position would result in a clear rather than amber light output, which may not meet regulatory requirements for turn signal color.
The 21W power rating at 12V places both bulb types in the standard incandescent range for automotive turn signal applications, drawing approximately 1.75 amperes per bulb under normal operating voltage.