BMW 323i Dome Light Bulb Size

The BMW 323i dome light requires bulb size DE3423 or 6411 depending on the specific version of the vehicle. Data for the lighting components covers the range from 1998 to 2000.

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
1999-2000	DE3423
1998	6411

Bulb Specifications

Description	Bulb Size
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 DE3423 is a festoon-type bulb with a 41mm length and end-cap contacts, operating at 12V. It follows the ANSI standard applicable in the US and Canada.
The 6411 is also a festoon-type bulb, though shorter at 36mm, and uses an SV8.5 base rather than end-cap contacts. It is rated at 12V and 5W, and likewise conforms to the ANSI standard for the US and Canada.
Both bulb types share the festoon form factor, meaning they are cylindrical bulbs that mount between two contact points within a housing. Despite this shared form factor, the DE3423 and 6411 differ in length and base type, making them non-interchangeable.
The BMW 323i (1999-2000) uses the DE3423 for the dome light, while the 1998 model year uses the 6411. The change in bulb type between the 1998 and 1999 model years reflects a difference in the dome light housing design across those production periods.