This 2017 Audi A4 bulb size guide helps you verify the correct bulbs by lighting position, so you can match the right part to the right socket before you buy. Because Audi used different lighting setups depending on trim, market, and package, checking the location on the vehicle is the safest way to confirm fitment.
For the 2017 Audi A4, many exterior and interior positions use LED lighting, while a few locations may still use specific halogen-style bulbs or HID-related parts depending on equipment. Use this page to compare the headlight, brake, turn signal, reverse, license plate, and cabin light positions for a more accurate replacement search.
Fitment can vary a lot on the 2017 Audi A4 based on body style, trim level, lighting package, and whether the car came with halogen, HID, or LED headlights. That means two A4s from the same year may not use the same bulb in every location. If you are considering an aftermarket conversion, make sure the bulb type, connector, and housing are compatible, especially for headlight and turn signal applications. The best practice is to inspect the installed bulb before ordering, since the physical bulb code on the old part is the most reliable confirmation when the catalog listing is unclear.
