The Volvo V50 side marker utilizes a specific 12961 bulb size for illumination purposes within the exterior lighting assembly. Available data for the specified component covers the period from 2005 through 2011.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volvo V50 uses two distinct bulb types across its side marker positions: the 12961 for the front and the P21/5W for the rear, covering the full 2005-2011 model range.
The 12961 is a Philips part number designating a miniature wedge-style T10 bulb with a W2.1x9.5d base, rated at 12V and 5W.
The T10 wedge base relies on friction contact rather than a locking mechanism, meaning the bulb is held in place by the socket walls alone.
The P21/5W is an ECE-standard dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21W main filament and a 5W secondary filament.
The BAY15d base features two offset pins at different heights, a design that prevents incorrect insertion and ensures the correct filament is assigned to the correct circuit.
The dual-filament construction of the P21/5W means the rear side marker position on the Volvo V50 (2005-2011) shares a single bulb across two electrical functions, each served by a separate filament.
The 12961 and P21/5W are not interchangeable with each other, as they differ in base type, wattage, filament count, and physical form factor.
The W2.1x9.5d base designation on the 12961 is an IEC standard code, where "W" denotes a wedge base and the numeric values describe the pin spacing and insertion depth.