The Mercedes-Benz 500E brake light requires a P21W bulb size for proper installation and function within the lighting assembly. Data for the specific component covers the range from 1992 to 1993.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The P21W is the sole bulb type specified across all brake light positions on the Mercedes-Benz 500E, covering both the standard brake lights and the center high mount stop light for 1992-1993.
The P21W follows the ECE (Economic Commission for Europe) standard, a regulatory framework adopted across Europe and numerous other markets worldwide, governing bulb performance and construction.
As a single-filament bulb, the P21W is dedicated to one function only, which in this application is braking signal output rather than a combined stop and tail operation.
The P21W uses a BA15s bayonet base, where "BA" denotes a bayonet cap, "15" refers to the 15mm base width, and the lowercase "s" indicates a single contact at the base, distinguishing it from the dual-contact BA15d variant.
The bulb operates at 12 volts and consumes 21 watts, values consistent with standard automotive low-voltage electrical systems.
The BA15s base is not interchangeable with the BA15d base despite sharing the same 15mm width, as the number of contact points differs between the two types.