The 2017 Ford Focus ST uses different headlight bulb options depending on the installed headlight configuration. The listed low-beam choices are D3S and H11, while high-beam applications use H1 or D3S. Confirm whether the vehicle has the relevant HID or other headlight setup before ordering, as these options are not interchangeable.
- Fog lights use H8 LED bulbs.
- The daytime running light uses H1.
- Front turn signals use 7507 on hatchbacks with HID headlights.
- Rear turn signals vary by body style: 3757A for hatchbacks and 3157A for sedans.
- Brake and tail lights use 3157R; reverse lights use 921.
- Parking lights use 168, with 2827 front and 194NA rear side-marker bulbs.
Verify the body style and headlight equipment against the existing bulb or vehicle configuration before purchase.