Kia Niro EV Turn Signal Bulb Size

Additional Notes

• The PY21W is an ECE-standard single-filament amber bulb rated at 12 volts and 21 watts, fitted with a BAU15s bayonet base. The amber tint is built into the glass envelope itself, which allows the bulb to produce the legally required amber signal color without relying on a colored lens.
• The BAU15s base uses offset pins, distinguishing it from the more common BA15s base whose pins are symmetrically placed. This offset prevents a non-amber bulb with a standard BA15s base from being seated in a socket designated for the PY21W, serving as a physical interchangeability safeguard.
• The Kia Niro EV uses the PY21W for its rear turn signal across the 2023-2024 model years.