The Lexus IS350 dome light requires bulb sizes 12961, 6428, and 13050 depending on the specific version of the vehicle. Data for the interior lighting components covers the range from 2006 to 2021.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 12961 is a Philips part number for a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. It is the most frequently referenced bulb across the Lexus IS350 dome light specifications, appearing in the general dome light, front dome light, and rear dome light positions.
The T10 wedge form factor appears under two separate part numbers in these specifications: the 12961 (5W, Philips) and the 194 (3.78W, ANSI standard). Although both share the T10 designation, their wattage ratings differ, and they are listed for distinct model years and positions rather than as interchangeable alternatives.
The 6428 is an ANSI-standard festoon bulb with an SV8.5 base and a 36mm length, rated at 12V and 5W. It is specified for the general dome light position on the IS350 for the 2006 and 2008-2009 model years.
The DE3022 is an ANSI-standard festoon bulb with end-cap contacts, rated at 12V, and measures 31mm in length. It differs from the 6428 in both length and contact type, making the two festoon bulbs non-interchangeable despite sharing a similar form factor.
The 194 is an ANSI-standard T10 miniature wedge bulb rated at 12V and 3.78W. It is specified for the front dome light position on the IS350 for the 2006-2009 model years.
The 13050 is identified as an OEM and Wagner part number for a halogen bulb in a specialty application, rated at 12V. It appears only in the general dome light position for the 2007 model year, where neither the 6428 nor the 12961 is listed for that same position and year.
The W2.1x9.5d base designation on the 12961 refers to a specific wedge base standard where the pin spacing and body width are precisely defined, which affects physical fitment into the bulb socket.
The SV8.5 base on the 6428 denotes a festoon-style holder where the bulb is retained by spring contacts at each end of the cylindrical body, a mounting method distinct from the end-cap contact design used by the DE3022.
For the 2017-2019 model years, the front and rear dome light positions on the IS350 both specify the 12961, while the general dome light entry for those years is absent from the provided data, with 2016 and 2021 each listing the 12961 for the general position.
The shift from the 6428 in the general dome light position for 2006 and 2008-2009 to the 12961 for 2016 and 2021 reflects a change from a festoon-style fitment to a wedge-style fitment across those model years, indicating the two bulb types are not cross-compatible for that position.