Mercedes-Benz E550 Map Light Bulb Size

The Mercedes-Benz E550 map light utilizes 12961 and H6W bulb sizes for the interior lighting components. Available data covers the range from 2007 through 2017 for the specified vehicle and lighting equipment.

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
2008-2017	12961
2007	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 E550 map light uses the 12961 bulb across the 2008-2017 model years, while the 2007 model year uses the H6W bulb instead.
The 12961 is a Philips part number designating a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W.
The T10 wedge base is one of the most common bulb formats in automotive interior lighting, relying on friction fit rather than a locking mechanism to seat in the socket.
The H6W is an ECE-standard bulb, meaning it conforms to European and international regulations for signalling applications. It carries a BAX9s base and is rated at 12V and 6W.
The BAX9s base used by the H6W is an offset pin base, which is not interchangeable with the W2.1x9.5d wedge base of the 12961. The two bulbs are physically incompatible despite sharing the same 12V operating voltage.
The 2007 Mercedes-Benz E550 map light socket accepts the BAX9s base of the H6W, which means a 12961 wedge bulb cannot be substituted without a socket adapter or modification.
The wattage difference between the two bulbs is minor, with the H6W drawing 6W and the 12961 drawing 5W, but the base incompatibility remains the primary fitment concern when considering substitution.