BMW 320i front and rear side marker bulbs utilize a 3893 bulb size for both locations. The replacement chart covers 1977 to 1983 model 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 BMW 320i uses the 3893 bulb for both front and rear side marker positions across the 1977-1983 model years.
The 3893 is classified as an ANSI standard bulb, meaning it conforms to a defined North American specification recognized in the United States and Canada.
The 3893 operates at 12 volts, which is consistent with the standard electrical system voltage found in passenger vehicles of that era.
The 3893 is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope, allowing it to serve more than one lighting function.
The 3893 uses a BAY15d bayonet base, a two-pin offset base type where the two pins are positioned at different heights to ensure the bulb is inserted in only one orientation, preventing filament misalignment.
The 3893 is categorized as a specialty application bulb, indicating it is intended for specific fitments rather than general-purpose use.
The front and rear side marker positions on the BMW 320i share the same bulb specification across all listed model years, meaning a single bulb type serves both locations on the vehicle.