For the 2015 Audi S5, both the low-beam and high-beam headlights use D3S bulbs. The supplied fitment data does not list a separate bulb size or variation by headlight type, so D3S is the listed fitment for both functions.
- Fog lights: LED
- Front turn signals: 64132
- Reverse lights: 921
- Brake, center stop, daytime running, parking, tail, and rear turn signals: LED
- Interior lighting: Dome lights use 6411 or 6428; glove box, interior, map, reading, and trunk lights use 2825 or 98.
- Vanity lights: 6418
LED-equipped locations are listed as LED rather than with a replaceable bulb code. For the headlamps, verify the existing bulb labeling and connector before ordering replacement D3S bulbs.