Volvo V40 Dome Light Bulb Size

The Volvo V40 dome light requires bulb size 6411 or DE3423 depending on the specific version of the component. Data for the lighting specifications covers the range from 2000 to 2004.

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
2004	6411
2001-2003	DE3423
2000	6411

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 36mm length, SV8.5 base. 12V, 5W.	6411
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

Both bulb types specified for the Volvo V40 dome light are festoon-style bulbs, a form factor characterized by a cylindrical tube with contacts at each end, designed to mount between two spring-loaded clips inside a dome light housing.
The 6411 bulb follows the ANSI standard applicable to the US and Canadian markets, measures 36mm in length, uses an SV8.5 base, and operates at 12V with a 5W rating.
The DE3423 bulb also follows the ANSI standard for US and Canadian markets, measures 41mm in length, uses end-cap contacts rather than an SV8.5 base, and operates at 12V.
The 5mm difference in length between the 6411 and the DE3423 is a critical fitment factor, as festoon bulbs must physically span the contact points of the housing to seat correctly.
The SV8.5 base of the 6411 and the end-cap contacts of the DE3423 represent two distinct contact configurations, meaning the two bulbs are not interchangeable despite both being festoon types.
The Volvo V40 (2000) and the 2004 model year both specify the 6411 bulb for the dome light position.
The 2001-2003 model years specify the DE3423 bulb for the same dome light position.
The shift between bulb types across model years indicates that the V40 dome light housing specification changed at some point in the production run, making year-specific verification necessary before replacement.