The Kia Niro brake bulb specifications include a P21/5W size for the outer brake bulb and a 194 size for the inner brake bulb. The replacement chart covers vehicle production years from 2018 to 2022 with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The P21/5W is the most frequently specified bulb across the Kia Niro brake light positions covered in these specifications. It follows the ECE standard used in Europe and worldwide markets, operating at 12V with a dual-filament design rated at 21W and 5W respectively. The higher-wattage filament serves the brake function, while the lower-wattage filament serves a secondary role such as a tail or parking light.
The P21/5W uses a BAY15d bayonet base, which is an offset twin-pin fitting. The offset pin placement is a deliberate design feature that prevents incorrect installation by ensuring the bulb can only be inserted in one orientation, keeping the two filaments correctly aligned with their intended circuits.
The 194 bulb is specified for the Inner Brake position on the 2021-2022 Kia Niro. It follows the ANSI standard used in the US and Canada, and is a miniature wedge-type bulb in the T10 form factor, operating at 12V and 3.78W.
The P21/5W and 194 are not interchangeable. They differ in base type, wattage, filament count, and regulatory standard. The P21/5W uses a bayonet base with dual filaments, while the 194 uses a wedge base with a single filament at a significantly lower wattage.
The Inner Brake position on the 2021-2022 Kia Niro uses the 194 wedge bulb rather than the P21/5W specified for the main brake position, indicating that the two positions require separate and distinct bulb types despite serving related lighting functions.