For the 2004 Subaru Impreza, the high-beam headlight uses a 9005 bulb. Low-beam fitment depends on the configuration: the Outback uses H1, while the WRX STI uses D2R. Confirm the trim and original headlamp setup before ordering, particularly for the STI.
- Fog lights may use H3 or H3C; compare the existing bulb and socket when replacing them.
- Front turn signals and reverse lights use 7440 bulbs.
- Brake-light fitment differs by body style: the sedan uses 7440R, while the wagon uses 7443R.
- The rear turn signal uses 7440A, with the wagon also listed for 1156A.
- The center stop light uses 921, or 912 on the Outback.
- Interior lighting includes DE3175 for both the dome and map lights. The trunk light is listed as 921, with 912 also noted as an option.