The Mercedes-Benz C320 high beam headlight uses an H7 bulb size, while low beam headlights accommodate H7, D2S, or D2R bulb sizes. The replacement chart covers 2001 to 2005 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The H7 bulb is a single-filament halogen type operating at 12V and 55W, fitted with a PX26d base. It serves as the high beam bulb across all model years of the Mercedes-Benz C320 from 2001-2005, and also functions as the low beam bulb in non-HID configurations throughout the same range.
The D2S and D2R are both HID (xenon) discharge bulbs rated at 85V and 35W. Despite sharing the same wattage and voltage, they are not interchangeable, as each is designed for a specific housing type and carries a different base fitting.
The D2S uses a P32d-2 base and is intended for projector-type headlamp housings. It appears as the HID low beam option for the C320 in 2003-2005.
The D2R uses a P32d-3 base and is designed for reflector-type headlamp housings. It is listed as the HID low beam option for the C320 in 2001-2002, making it a distinct fitment from the D2S used in later years.
Both D2S and D2R bulbs require an external ignitor to initiate the high-voltage arc necessary for operation. This is a fundamental characteristic of HID discharge technology, distinguishing it from the self-contained nature of halogen bulbs.
All three bulb types, H7, D2S, and D2R, conform to ECE standards, which are recognized across Europe and worldwide, and the H7 additionally holds approval in the United States and Japan.
For the 2001 low beam position, the halogen fitment is specifically noted as applying to vehicles with halogen capsule headlamps, while the D2R applies to those with HID headlamps. This explicit notation reflects a factory-level distinction between two separate headlamp assemblies.
The shift from D2R to D2S for HID low beams between the 2002 and 2003 model years indicates a change in headlamp housing design, since the two bulb types are housing-specific and cannot be substituted for one another.