The Mercedes-Benz 380SEC uses a P21/5W bulb size for the front turn signal and a P21W bulb size for the rear turn signal. The replacement chart covers 1982 to 1983 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 Mercedes-Benz 380SEC uses two distinct ECE-standard bulb types across its front and rear turn signal positions for the 1982-1983 model years.
The P21/5W is a dual-filament bulb rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base.
The BAY15d base features offset pins, a design that prevents incorrect insertion by ensuring the bulb can only be seated in one orientation.
The P21W is a single-filament bulb rated at 12V and 21W, mounted on a BA15s bayonet base, which uses a single contact at the base tip.
The front turn signal position on the 380SEC calls for the P21/5W across both the 1982 and 1983 model years.
The rear turn signal position on the 380SEC calls for the P21W across both the 1982 and 1983 model years.
The P21/5W and P21W are not interchangeable despite sharing a similar wattage rating on their primary filaments, as they differ in base type and filament configuration.
Both bulb types conform to ECE regulations, a lighting standard recognized across Europe and numerous other markets worldwide.