The Mercedes-Benz 500SEC front side marker bulb uses a 2357NA or P21/5W size, while the rear side marker bulb requires a P21/4W or 3893 size. The replacement chart covers 1984 to 1993 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 500SEC uses dual-filament bulbs across all listed side marker positions and model years, meaning each bulb contains two separate filaments that operate at different wattages for distinct lighting functions.
The front side marker for the 1993 500SEC takes a 2357NA bulb, which follows the ANSI standard used in the United States and Canada. It operates at 12V with a high-filament draw of 26.9W and a low-filament draw of 8W, and its natural amber glass produces a color-tinted output without requiring an amber lens.
The front side marker for 1984-1985 uses a P21/5W bulb, an ECE-standard type common in European and worldwide markets. It operates at 12V with filament ratings of 21W and 5W.
Both the 2357NA and the P21/5W share a BAY15d bayonet base, which is an offset dual-contact base. Despite this shared base type, the two bulbs are not interchangeable due to differences in wattage, glass color, and regulatory standards.
The rear side marker for the 1993 500SEC uses a P21/4W bulb, which is an ECE-standard type operating at 12V with filament ratings of 21W and 4W. Its base is a BAZ15d, which differs from the BAY15d base found on the other bulbs in these specifications.
The BAZ15d base on the P21/4W has its dual contacts positioned at a different offset than the BAY15d base. This physical difference prevents a P21/4W from being seated in a BAY15d socket, making it mechanically distinct from the other bulbs listed.
The rear side marker for 1984-1985 uses a 3893 bulb, an ANSI-standard type with a BAY15d bayonet base rated at 12V. It is classified as a specialty application bulb within the ANSI system.
The front and rear side markers on the 1993 500SEC use bulbs from different regulatory standards, with the front position following ANSI and the rear following ECE. This means the two positions on the same model year are not served by interchangeable bulbs.
For 1984-1985, the front and rear side markers also use non-interchangeable bulbs. The front uses a P21/5W with a BAY15d base, while the rear uses a 3893, also with a BAY15d base, but the two differ in wattage ratings and application classification.