Audi S5 License Plate Bulb Size

Additional Notes

• The DE3423 is the sole bulb type listed for the license plate position across all specified model years of the Audi S5.
• The years covered by these specifications span 2008-2012, with the DE3423 bulb size remaining consistent throughout that entire period.
• The DE3423 is a festoon-type bulb, meaning it is cylindrical in shape and makes electrical contact through metal caps at each end rather than through a base socket or pins.
• Festoon bulbs are held in place by spring-loaded clips within the lamp housing, which grip the end caps to maintain both physical retention and electrical connection.
• The DE3423 has a specified length of 41mm, which is a critical fitment factor, as festoon bulbs must match the span between the spring clips in the housing to seat correctly.
• The bulb operates on a 12-volt electrical system, consistent with standard automotive low-voltage architecture.
• The DE3423 carries ANSI standardization recognized in both the United States and Canada, meaning the specification conforms to a defined North American industry standard rather than a proprietary designation.
• Because the DE3423 is an ANSI-standardized part, bulbs from different manufacturers carrying the same designation are expected to share the same physical and electrical characteristics, provided they meet the standard.
• Festoon bulbs of differing lengths are not interchangeable even when voltage ratings match, as an incorrect length will prevent proper contact with the housing clips or cause mechanical stress on the lamp assembly.