The Mercedes-Benz GL320 high beam headlight uses an H7 bulb size, while low beam headlights accommodate H7, D1S, or D2S bulb sizes. The replacement chart covers 2007 to 2009 production 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 H7 is a single-filament halogen bulb operating at 12V and 55W, built to ECE standards and approved for use in Europe, the US, Japan, and worldwide. It uses a PX26d base, which is a two-pin bayonet-style connector specific to the H7 format.
The Mercedes-Benz GL320 uses the H7 bulb across all three model years (2007-2009) for the high beam headlight position, making it the most consistently specified bulb type across the entire dataset.
The H7 also serves as the low beam bulb on GL320 vehicles equipped with halogen capsule headlamps across all three years (2007-2009), meaning a single bulb type covers both beam positions on halogen-equipped vehicles.
Two distinct HID bulb types appear in the low beam specifications depending on the model year. The 2007 GL320 with HID headlamps uses the D2S, while the 2008-2009 GL320 with HID headlamps uses the D1S. These two bulbs are not interchangeable despite sharing the same 85V, 35W operating ratings.
The D1S and D2S differ in their ignitor configuration. The D1S integrates the ignitor directly into the bulb body and uses a PK32d-2 base, while the D2S uses a P32d-2 base and relies on a separate external ignitor mounted in the housing.
Both the D1S and D2S are specified for projector-type housings, which use a lens and cutoff shield to shape the light beam. Substituting either HID bulb into a non-projector housing would alter the beam pattern.
The D1S and D2S operate at 85V arc voltage, which is substantially higher than the 12V supply voltage of the vehicle's electrical system. A ballast is required to convert and regulate the power supply for both bulb types.
All bulb types listed across the GL320 specifications conform to ECE regulations, the international lighting standard used in Europe and most global markets, and are also recognized in the US and Japan.