Mercedes-Benz GL450 License Plate Bulb Size

The Mercedes-Benz GL450 license plate light requires 12961 and DE3423 bulb sizes for the rear exterior illumination. Data for the specified lighting components covers the range from 2007 through 2012.

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
2012	12961
2007-2011	DE3423

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, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

The DE3423 is an ANSI-standardized festoon bulb used in the Mercedes-Benz GL450 across the 2007-2011 model years for the license plate position. Festoon bulbs are cylindrical in form and make electrical contact through metal caps at each end rather than through a base socket.
The 2012 Mercedes-Benz GL450 uses the 12961 bulb, a Philips-designated miniature wedge type, in place of the festoon format used in prior years. This represents a change in bulb category between the 2011 and 2012 model years.
The 12961 operates on a T10 wedge base with a W2.1x9.5d designation, which describes the contact pin spacing and base width. It runs at 12 volts and draws 5 watts.
Because the 2012 model year uses a wedge-base bulb and the 2007-2011 model years use an end-cap festoon bulb, the two bulb types are not interchangeable. The socket and retention method differ between the two formats.
The DE3423 festoon bulb has a 41mm length, which is a standard festoon size. Festoon bulbs of differing lengths are not compatible with one another, as the end caps must span the exact distance between the socket contacts.
The DE3423 carries ANSI standardization applicable in both the United States and Canada, meaning equivalent bulbs from different manufacturers conforming to that standard share the same physical and electrical characteristics.
Both bulb types operate at 12 volts, consistent with standard automotive electrical systems. The 12961 is rated at 5 watts, placing it in the low-wattage range typical of license plate illumination.