Alfa Romeo Stelvio Turn Signal Bulb Size

Additional Notes

• The PY24WNA bulb is the sole front turn signal type listed across all Alfa Romeo Stelvio model years in the specifications, covering 2018-2023.
• PY24WNA operates at 12 volts and 24 watts, placing it in a moderate wattage range typical of dedicated turn signal applications.
• The PY24WNA designation follows the ANSI standard applicable to the United States and Canada markets, distinguishing it from its ECE counterpart, the PY24W.
• Although the PY24WNA is derived from the ECE PY24W, the two are not interchangeable without verification, as ANSI and ECE standards govern different regulatory markets and may involve physical or electrical differences.
• The bulb uses a PGU20-4 base, a wedge-type bayonet fitting specific to amber signal bulbs, which prevents substitution with clear bulbs sharing otherwise similar bases.
• The amber coloration is built into the PY24WNA bulb itself rather than relying on a colored lens, a construction method associated with improved signal visibility and regulatory compliance in North American markets.
• For the 2018-2020 Alfa Romeo Stelvio, the PY24WNA fitment is conditioned on the presence of Halogen Capsule Headlamps, indicating that alternative headlamp configurations on those model years may require a different front turn signal bulb.
• The 2021-2023 Stelvio carries no headlamp configuration qualifier for the PY24WNA, reflecting an unconditional fitment for those years.