The BMW 428i Gran Coupe high beam headlight uses D1S and H7 bulb sizes, while the low beam headlight requires a D1S bulb size. The replacement chart covers 2015 to 2016 model 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 BMW 428i Gran Coupe uses two distinct headlight technologies across its 2015-2016 model years: HID (high-intensity discharge) xenon systems and halogen capsule systems, depending on the factory-installed headlamp configuration.
The D1S bulb serves both the high beam and low beam positions in HID-equipped 428i Gran Coupe models for 2015-2016, meaning a single bulb type handles both functions within the projector-type housing.
The D1S operates at 85 volts and 35 watts. It follows the ECE standard used in Europe and worldwide, features a PK32d-2 base, and incorporates an integral ignitor, which is a self-contained component that initiates the high-voltage arc required to strike the xenon discharge.
Because the D1S includes a built-in ignitor, it is not interchangeable with other HID bulb types such as D1R or D3S, which differ in base configuration, ignitor placement, or shield design despite sharing similar wattage ratings.
Halogen-equipped 428i Gran Coupe models for 2015-2016 use the H7 bulb exclusively in the high beam position. The low beam position in halogen configurations is not covered by these specifications.
The H7 is a single-filament halogen bulb rated at 12 volts and 55 watts with a PX26d base. Its ECE certification is recognized in Europe, the United States, and Japan, making it one of the more broadly approved bulb standards across major automotive markets.
The H7 and D1S are not interchangeable. They differ in operating voltage, base type, and the underlying technology of the light source, and each requires a headlamp housing specifically engineered for that bulb type.
Selecting the correct replacement bulb for the 428i Gran Coupe requires confirming whether the vehicle was built with HID or halogen capsule headlamps, as both configurations were available across the same 2015-2016 production span.