Mercedes-Benz C300 high beam headlight uses H7 bulb size while low beam headlight uses H7 or D1S bulb size depending on configuration. The chart covers replacement bulb sizes across 2008 to 2019 model years.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The H7 bulb is the most prevalent type across these specifications, appearing in both the high beam and low beam positions of the Mercedes-Benz C300 for model years 2008-2019. It is a halogen bulb operating at 55 watts with a PX26d base, designed for single-filament applications in dedicated beam housings.
The high beam headlight position uses the H7 bulb exclusively across all listed model years, 2008-2019, with no alternative bulb types specified for that position.
The low beam headlight position for model years 2008-2014 carries two distinct bulb size entries: H7 and D1S. The D1S entry is qualified with the condition "With HID Headlamps," indicating a trim or factory option dependency rather than a universal fitment.
The D1S is a High-Intensity Discharge (HID) bulb that operates through an electrical arc between two tungsten electrodes within a xenon gas-filled quartz capsule. It requires a ballast to regulate the high-voltage ignition and sustained arc current, making it electrically and mechanically incompatible with standard halogen sockets.
Because the H7 and D1S operate on fundamentally different electrical systems, the two low beam options listed for 2008-2014 are not interchangeable. The correct bulb type depends entirely on whether the vehicle was equipped with HID headlamps at the factory.
The D1S bulb uses an integrated igniter within the bulb body itself, distinguishing it from D2S and D3S types where the igniter is housed separately in the ballast or socket. This makes D1S units non-interchangeable with other D-series HID types even when wattage ratings are similar.
For model years 2015-2019, the low beam headlight specifications list only the H7 bulb, with no HID variant noted for those years.
The H7 bulb's PX26d base is a keyed, single-pin bayonet-style connector. Housings designed for H7 fitment incorporate a specific retention tab and socket orientation that prevents substitution with physically similar halogen types such as H1 or H11.