BMW X2 front turn signal uses 2357NA bulb size while rear turn signal requires P21W bulb size. The chart covers replacement specifications from 2018 to 2023.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 2357NA bulb is an ANSI-standard dual-filament type rated at 12V with a high filament draw of 26.9W and a low filament draw of 8W. It uses a BAY15d bayonet base and features natural amber glass, which produces the amber signal color without requiring a tinted lens.
The P21W is an ECE-standard single-filament bulb rated at 12V and 21W. It uses a BA15s bayonet base, which is a single-contact variant and is not interchangeable with the dual-contact BAY15d base used by the 2357NA.
The BMW X2 uses the 2357NA for the front turn signal across the 2018-2023 model years. The 2020 model year carries an explicit notation that this fitment applies specifically to vehicles equipped with halogen capsule headlamps.
The rear turn signal on the BMW X2 uses the P21W across the full 2018-2023 model year range.
Because the front and rear turn signals use bulbs from different international standards bodies (ANSI and ECE respectively), the two bulb types are not interchangeable with each other, despite both operating on a 12V system.
The BAY15d base of the 2357NA has two offset pins that prevent incorrect single-filament bulbs from being seated in its socket, a physical safeguard tied to the dual-filament design.