Parts for your 2010 Subaru Impreza-Exterior bulbs

2010 Subaru Impreza Exterior Bulbs: What They Do and How to Look After Them

Exterior bulbs are absolutely relevant and fitted to the 2010 Subaru Impreza. Technical references, including the Subaru Owner’s Manual for MY2010 Impreza and application catalogues from major lighting makers (Osram, Philips, and Sylvania), confirm the vehicle uses replaceable exterior bulbs across the headlights, fog lights, indicators, park/position lamps, brake and tail lamps, reverse lamps, and number plate lights.

On this model, most trims run halogen globes: typically H11 for low beam, 9005 (HB3) for high beam, and H11 for front fogs. Around the car you’ll usually find W5W/T10 for parkers and number plate, 7443 for brake/tail, 7440A (amber) for indicators, and 921/W16W for reverse. Exact types can vary with body style and trim (and some WRX/STI variants in certain markets may have factory HID low beams), so checking the owner’s manual or the bulb label on the housing is the go.

Their purpose is straightforward: see and be seen, meet ADR/NZTA lighting requirements, and keep the Impreza safe and legal. Dull, mismatched, or blown bulbs can cop a defect, fail a WoF, and reduce visibility in poor weather. During servicing, it’s worth inspecting all exterior lights, cleaning the lenses, and replacing any tired bulbs in pairs so beam colour and brightness stay even.

• Inspection: Give the lights a quick check monthly, and at each service or every 10,000 km. Look for dimming, flicker, or moisture in the housings.
• Replacement tips:
  • Use the correct 12V type and wattage (e.g., H11, 9005, 7443). Avoid “overwattage” globes that can melt housings.
  • Don’t touch the glass of halogen bulbs with bare fingers, oils cause hot spots and early failure.
  • Seat the bulb fully, refit dust caps/seals, then test all functions.
• DIY access:
  • Headlights/fogs: Access from behind the housing, twist the holder anticlockwise, swap the globe, click back in.
  • Rear lamps: Open the boot, pop off the trim panel, twist the bulb holder, replace, and refit.
• Aftercare: Check headlight aim after replacement. Persistent failures may point to a charging/earth fault or water ingress—worth a proper diagnostic.

Bulb life varies with driving and vibration, but two to five years is typical for halogen. For long trips or rural driving, carrying a small spare bulb kit is a smart bit of insurance.

Popular questions about 2010 Subaru Impreza exterior bulbs

What bulb sizes does a 2010 Subaru Impreza use?
Most trims commonly use H11 low beam, 9005 (HB3) high beam, H11 fog, T10/W5W parkers and plate lamps, 7443 brake/tail, 7440A front/rear indicators, and 921/W16W reverse. Trims and markets can vary, and certain WRX/STI variants may run HID low beams, so it’s best to confirm against the owner’s manual or the label on each lamp housing.

How often should the exterior bulbs be replaced?
There’s no hard interval—replace on failure or noticeable dimming. Inspect all lights at each service or every 10,000 km, clean lenses, and replace headlight pairs together to keep colour and brightness matched. If you’re driving lots of night kilometres or on rough roads, consider more frequent checks.

Why do new bulbs keep blowing?
Common culprits are touching the glass during install, incorrect wattage, poor earths, moisture inside the housing, or charging-system overvoltage. Check seals and caps for leaks, ensure the alternator is charging around 13.8–14.5 V with lights on, and verify good grounds. If the issue persists, have a tech test the circuit and connectors.