Audi A5 Sportback Turn Signal Bulb Size

Additional Notes

• The 12174NA is an OEM part number designating a natural amber glass bulb operating at 12 volts. The amber coloring is built into the glass itself rather than achieved through a coating, which produces the legally required amber turn signal output without relying on a clear lens filter.
• The 12174SV is a Philips SilverVision part number designating an enhanced coating halogen bulb also rated at 12 volts. The SilverVision coating gives the bulb a silvered appearance when unlit, while still producing the required amber output when energized.
• Both the 12174NA and 12174SV share the same base numerical designation of 12174, indicating they occupy the same physical socket position in the Audi A5 Sportback front turn signal housing.
• Despite sharing the same socket fitment, the 12174NA and 12174SV are distinct product variants and are not identical in construction. The 12174NA uses natural amber glass, while the 12174SV relies on a surface coating to achieve its visual effect.
• The 2024 and 2023 Audi A5 Sportback front turn signal position uses the 12174NA bulb. The 2021 model year uses the 12174SV for the same position, indicating that different factory-specified variants have been applied across model years for the same socket.
• The 2019 and 2018 Audi A5 Sportback front turn signal specifications for the 12174NA are conditioned on the presence of HID headlamps, meaning this fitment applies specifically to vehicles equipped with that headlamp type.