Audi RS3 Turn Signal Bulb Size

The Audi RS3 turn signal requires a bulb size of PY21W for the lighting components. Data for the specific bulb requirements covers the range from 2023 to 2024.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2023-2024	PY21W

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament amber bulb with BAU15s bayonet base. 12V, 21W.	PY21W

Other Locations

Additional Notes

The PY21W is the turn signal bulb type specified for the Audi RS3 across the 2023-2024 model years.
The PY21W operates on a 12-volt electrical system and draws 21 watts, placing it in the single-filament category standard for dedicated turn signal applications.
The bulb produces amber light natively, meaning the lens housing does not need to filter a clear bulb to achieve the legally required turn signal color.
The PY21W uses a BAU15s bayonet base, which has offset pins that distinguish it physically from the more common BA15s base. This offset prevents incorrect installation of non-amber bulbs into the socket.
The PY21W is rated under the ECE standard, a regulatory framework recognized across Europe and numerous other markets worldwide.