For the 2013 Cadillac ATS, headlight bulb fitment depends on the factory headlight type. Models with halogen headlights use a 9012 bulb for both the low beam and high beam. Models equipped with HID headlights use a D3S bulb for both functions. Confirm the headlight configuration before ordering, since these bulbs are not interchangeable.
- Front turn signals and parking lights use 7444NA bulbs.
- Front side markers use 194NA.
- Reverse lights use 921.
- Brake lights, tail lights, rear turn signals, rear side markers, center stop light, and daytime running lights are listed as LED.
- License plate lighting may use 2825 or 98, depending on the lamp assembly.
- Interior, trunk, and step lighting may use 194 or 7441; vanity lighting uses 7065.