The Mercedes-Benz C350 front fog light uses H7, H11, or 9006 bulb sizes, while the rear fog light requires a P21W bulb size. The replacement chart covers 2006 through 2011 model years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mercedes-Benz C350 front fog light specification lists three distinct bulb types across the 2006-2011 model years: H7, H11, and 9006. These types are not interchangeable despite sharing the same 12V, 55W electrical rating, as each uses a physically different base configuration.
The H7 bulb, which uses a PX26d base, is the most frequently specified front fog light bulb for the C350, appearing in the 2008, 2010, and 2011 model years.
The 9006 bulb follows an ANSI standard and uses a P22d base. It is specified for the 2006-2007 C350 front fog lights. Although its wattage and voltage match the H7 and H11, its P22d base is mechanically distinct from the PX26d base of the H7 and the PGJ19-2 base of the H11.
The H11 bulb, which uses a PGJ19-2 base, is specified exclusively for the 2009 C350 front fog light. It operates at 12V and 55W, consistent with the other front fog light bulbs in the specification, but its base type differs from both the H7 and 9006.
The P21W bulb is specified for the rear fog light across all six model years covered, from 2006 through 2011. It operates at 12V and 21W, a notably lower wattage than the front fog light bulbs.
The P21W uses a BA15s bayonet base, which is a single-contact bayonet fitting. This base type is mechanically unrelated to the bases used in the front fog light positions.
The H7 and H11 bulbs both follow ECE standards, meaning they are approved for use in Europe, worldwide markets, the United States, and in the case of H7, Japan as well. The 9006 follows an ANSI standard applicable to the US and Canada.
The front fog light position of the C350 saw a bulb type change in three separate instances across the 2006-2011 span: from 9006 to H7 between 2007 and 2008, from H7 to H11 between 2008 and 2009, and from H11 back to H7 between 2009 and 2010.