The Mercedes-Benz ML55 AMG side marker requires a bulb with the specific 12961 size for proper installation. Available data for the specified component covers the period from 2000 through 2003.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The front side marker position on the Mercedes-Benz ML55 AMG uses two distinct bulb types across its production years: the 1034NA for 2000-2001 and 2003, and the 1157NA for 2002.
Both the 1034NA and 1157NA are ANSI-standard dual-filament bulbs sharing the BAY15d bayonet base and a 12V, 21W/5W power rating, with natural amber glass construction.
Despite their shared base type and near-identical wattage ratings, the 1034NA is a variant of the 1157NA rather than a direct equivalent, which is a relevant fitment consideration for the 2002 front side marker position.
The rear side marker position transitions between two bulb types across the model's production years: the P21/4W for 2000-2001 and the 12961 for 2002-2003.
The P21/4W is an ECE-standard dual-filament bulb with a BAZ15d bayonet base, rated at 12V and 21W/4W, and is classified as a signalling bulb under European and worldwide standards.
The 12961 is a Philips part number designation for a miniature wedge-style T10 bulb with a W2.1x9.5d base, rated at 12V and 5W, representing a single-filament design.
The rear side marker shift from the dual-filament P21/4W to the single-filament 12961 between the 2001 and 2002 model years reflects a significant change in both base type and wattage output, making the two bulbs non-interchangeable.
The BAY15d base used by the 1034NA and 1157NA features offset pins to ensure correct polarity orientation, a design detail relevant to dual-filament applications where each filament serves a separate lighting function.
The BAZ15d base of the P21/4W similarly uses an offset pin configuration, though it is a distinct standard from the BAY15d and is not physically compatible with sockets designed for the latter.