Mercedes-Benz CLK320 Map Light Bulb Size

The Mercedes-Benz CLK320 Map Light utilizes 12961 and H6W bulb sizes according to the provided technical specifications for the interior lighting components. Data for the specific bulb sizes covers the range from 1998 through 2005.

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
2000-2005	12961
1998-1999	H6W

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

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Additional Notes

The Mercedes-Benz CLK320 map light uses two distinct bulb types across its model years, with the H6W fitted in 1998-1999 models and the 12961 fitted in 2000-2005 models.
The 12961 is a Philips part number designating a T10 miniature wedge bulb operating at 12V and 5W, with a W2.1x9.5d base.
The H6W is an ECE-standard designation recognized across European and worldwide markets, identifying a single-filament signalling bulb rated at 12V and 6W, with a BAX9s base.
The W2.1x9.5d base of the 12961 and the BAX9s base of the H6W are physically incompatible with each other, as wedge bases and pin-type bayonet bases require different socket designs.
The BAX9s base used by the H6W is an offset single-pin bayonet fitting, a design that prevents incorrect bulb orientation during installation.
At 6W, the H6W draws slightly more power than the 12961 at 5W, meaning the two bulbs are not electrically equivalent despite both operating on a 12V system.
The T10 form factor of the 12961 is one of the most widely used miniature bulb formats in automotive interior lighting applications.
Because the 1998-1999 CLK320 uses the H6W and the 2000-2005 CLK320 uses the 12961, substituting one for the other across these year groups would require a socket adapter due to the differing base types.