BMW 320i Dome Light Bulb Size

The BMW 320i dome light utilizes bulb sizes 12961 and 6411 for interior illumination across various production periods. Data for the specified components covers the span from 1977 to 2018.

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
2013-2018	12961
1977-1983	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, 36mm length, SV8.5 base. 12V, 5W.	6411

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Additional Notes

The BMW 320i dome light specifications cover two distinct bulb types across the listed model years: the 12961 and the 6411.
The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor, fitted with a W2.1x9.5d base, rated at 12V and 5W.
The T10 wedge base design means the bulb is held in place by friction against the socket walls rather than by a bayonet or screw mechanism.
The 6411 follows the ANSI standard recognized in the US and Canada, classifying it as a festoon bulb with a 36mm length and an SV8.5 base, also rated at 12V and 5W.
A festoon bulb with an SV8.5 base is a cylindrical lamp that makes contact at both flat ends, a design common in interior dome and map light applications.
Despite sharing the same 12V, 5W electrical rating, the 12961 and 6411 use physically incompatible base types and are not interchangeable with each other.
The BMW 320i (2013-2018) uses the 12961 wedge bulb for the dome light position.
The 1977-1983 model years specify the 6411 festoon bulb for the same dome light position.
The W2.1x9.5d base designation on the 12961 reflects a metric standard, where the figures describe the contact pin width and spacing of the wedge base.