Mercedes-Benz SL65 AMG Map Light Bulb Size

The Mercedes-Benz SL65 AMG map light requires bulb size 12961, H6W, or DE3423 depending on the specific version. Data for the bulb sizes covers the range from 2005 to 2011.

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
2011	12961
2009	12961
2007-2008	H6W
2005-2006	DE3423

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ECE standard (Europe & worldwide). Single-filament signalling bulb with BAX9s base. 12V, 6W.	H6W
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

The Mercedes-Benz SL65 AMG map light specifications span three distinct bulb types across the 2005-2011 model years, with each type corresponding to a specific production period.
The 12961 is a Philips-designated miniature wedge bulb following the T10 form factor, fitted with a W2.1x9.5d base and rated at 12V, 5W. It appears in the 2009 and 2011 model years.
The W2.1x9.5d base is a wedge-style connector that relies on the bulb's wire leads pressing against socket contacts rather than a separate pin or bayonet mechanism, which makes it physically incompatible with sockets designed for pin or festoon contacts.
The H6W follows ECE standards, which govern lighting regulations across Europe and much of the wider world. It uses a BAX9s base, operates at 12V, and draws 6W, making it the highest-wattage bulb among the three types listed. It is specified for the 2007-2008 model years.
The BAX9s base features an offset single-pin design, which means orientation during installation is fixed. This base type is not interchangeable with the W2.1x9.5d wedge base used by the 12961, despite both bulbs operating at 12V.
The DE3423 follows ANSI standards applicable to the US and Canada. It is a festoon-type bulb with a 41mm length and end-cap contacts, rated at 12V. It is specified for the 2005-2006 model years.
Festoon bulbs make electrical contact through metal caps at each end of the cylindrical housing. This contact method is mechanically distinct from both the wedge base of the 12961 and the offset pin base of the H6W, making cross-substitution between these three types physically impractical without socket modification.
The three bulb types represent three separate base standards, meaning a bulb from one production period of the SL65 AMG is not a drop-in replacement for a bulb from a different period, even though all three operate on a 12V system.
The wattage values across the three types differ slightly, with the DE3423 having no wattage listed in the specifications, the 12961 rated at 5W, and the H6W rated at 6W. These differences reflect the distinct engineering standards each bulb type originates from.
The shift from DE3423 to H6W between the 2006 and 2007 model years of the Mercedes-Benz SL65 AMG represents a change from an ANSI-standard festoon format to an ECE-standard single-filament signalling format, reflecting a transition between two regionally distinct bulb classification systems.