BMW 325i Map Light Bulb Size

The BMW 325i map light uses bulb sizes 12961, DE3423, and 6411 according to the provided specifications for the interior lighting components. Available information covers a span of time starting from 1995 through 2006.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2002-2006	12961
2001	DE3423
1995	6411

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423
ANSI standard (US & Canada). Festoon bulb, 36mm length, SV8.5 base. 12V, 5W.	6411

Other Locations

Additional Notes

The BMW 325i map light bulb specifications cover model years 1995 and 2001-2006, with three distinct bulb types used across that span.
The 12961 is a Philips part number designation for a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. It is the map light bulb for the 325i across the 2002-2006 model years.
The T10 wedge form factor uses a plastic wedge base with integrated wire contacts rather than a separate metal base, which distinguishes it from festoon-style bulbs used in other 325i model years.
The DE3423 is an ANSI-standard festoon bulb with end-cap contacts and a 41mm length, rated at 12V. It is specified for the 2001 BMW 325i map light position.
The 6411 is also an ANSI-standard festoon bulb, rated at 12V and 5W, with an SV8.5 base and a 36mm length. It is specified for the 1995 325i map light position.
Festoon bulbs make contact at both ends of the cylindrical tube rather than through a side base, and the physical length is a critical fitment factor. The DE3423 at 41mm and the 6411 at 36mm are not interchangeable despite both being festoon-type bulbs.
The W2.1x9.5d base designation on the 12961 refers to a specific wedge base width and pin spacing standard, meaning it is not physically compatible with the festoon sockets used in the 1995 or 2001 325i.
The shift from a festoon bulb in 2001 to a T10 wedge bulb in 2002 reflects a socket change in the 325i map light housing, making cross-year substitution between those two generations incompatible without a socket adapter.