Audi A6 Dome Light Bulb Size

The Audi A6 dome light utilizes 6411 and DE3423 bulb sizes for the interior lighting components. Available information covers the span from 1995 through 2016 for the specified vehicle lighting data.

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
2009-2016	6411
2007-2008	6411 (From VIN 4F-7-000 001)
2006	6411 (To VIN 4F-6-250 000)
1998-2004	6411
1995-1997	DE3423

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

The Audi A6 dome light uses the 6411 bulb across the 1998-2016 model years, with the exception of 1995-1997, making it the dominant bulb type in these specifications.
The 6411 is a festoon-style bulb operating at 12 volts and 5 watts, with a 36mm length and an SV8.5 base, which is a center-contact barrel-type fitting common in interior automotive lighting.
The DE3423 is also a festoon bulb but measures 41mm in length and uses end-cap contacts rather than the SV8.5 center-contact base, making it physically and electrically incompatible with sockets designed for the 6411.
The Audi A6 (1995-1997) takes the DE3423 bulb for the dome light, while 1998 onward requires the shorter 6411, so the two types are not interchangeable despite both being festoon bulbs.
Both the 6411 and DE3423 are classified under the ANSI standard applicable to the US and Canadian markets.
For the 2007-2008 Audi A6, the 6411 bulb specification applies only to vehicles from VIN 4F-7-000 001 onward, indicating a mid-production fitment distinction within those model years.
The 2006 Audi A6 carries a corresponding VIN-based restriction, with the 6411 specification applying to vehicles up to VIN 4F-6-250 000.
The SV8.5 base designation on the 6411 refers to a festoon holder with a nominal 8.5mm cap width, a detail relevant when sourcing aftermarket or LED replacement bulbs, as base compatibility must be confirmed.
No wattage value is listed for the DE3423 in these specifications, whereas the 6411 is rated at 5 watts, a low draw consistent with interior courtesy lighting applications.
The 36mm length of the 6411 versus the 41mm length of the DE3423 represents a meaningful size difference; installing the longer DE3423 into a 36mm festoon socket would result in an improper fit.