Mercedes-Benz S600 Map Light Bulb Size

Additional Notes

• The Mercedes-Benz S600 map light specifications cover model years 1998-2013, with two distinct bulb types used across that span.
• The 12961 is a Philips part number designation for a T10 miniature wedge bulb. It uses a W2.1x9.5d base and operates at 12V with a 5W output.
• The H6W follows the ECE (Economic Commission for Europe) lighting standard, which is recognized across Europe and many other markets worldwide. It is a single-filament signalling bulb rated at 12V and 6W, fitted with a BAX9s base.
• The BAX9s base used by the H6W is an offset pin cap design, which physically prevents incorrect installation of incompatible bulbs into the same socket.
• The W2.1x9.5d base of the T10 (12961) is a wedge-type fitting, meaning the bulb is held in place by the tension of the socket contacts rather than by a locking pin or bayonet mechanism.
• The Mercedes-Benz S600 (2009-2013) uses the 12961 bulb for the map light position, while model years 1998-2007 and 2008 use the H6W.
• The two bulb types are not interchangeable. The W2.1x9.5d wedge base and the BAX9s pin base are mechanically incompatible with each other's sockets.
• The wattage difference between the two types is marginal, with the H6W rated at 6W and the 12961 at 5W, placing both within the low-wattage range typical of interior signalling and courtesy lighting applications.