For the 2014 Chevrolet Impala, 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.
The daytime running light also varies with the headlight configuration: halogen-equipped models use 9012, while HID-equipped models use LED. No fog light bulb fitment is listed for this vehicle.
Other notable exterior bulb applications include a 7444NA front turn signal and parking light, 7440 reverse lights, and 7443R brake lights. The center stop light is LED. Rear lighting can use several listed bulb types depending on the specific lamp application, including 194, 7441, and 7443R for the tail light, plus 7443 for the rear turn signal. Front and rear side markers use 194NA and 7443A, respectively. License plate lighting is listed with either 2825 or 98 bulbs.