The high-beam bulb is an H4 dual-filament bulb, also known as 9003.
In most 2005 Altima headlight assemblies, the high and low beams are managed by a single H4 (9003) bulb within a dual-filament design, though there can be variations by market or trim. Always verify with your owner's manual or by inspecting the bulb in your vehicle.
Bulb type and compatibility
Common options you’ll encounter when replacing the high-beam bulb in a 2005 Altima.
- H4/9003 dual-filament bulb — standard for many 2005 Altima headlight assemblies; provides both high and low beams in one bulb.
Bottom line: For most 2005 Altima models, plan to replace with H4/9003 dual-filament bulbs to maintain proper high-beam function.
Replacement guidance
How to replace the high-beam bulb safely and effectively.
- Turn off the engine and remove the keys; set the parking brake.
- Open the hood and locate the headlight assembly; remove the dust cap on the back of the housing.
- Disconnect the electrical connector from the bulb socket.
- Twist the H4/9003 bulb counterclockwise to release it from the housing and remove it.
- Install the new H4/9003 bulb, ensuring proper orientation with the tabs; reconnect the electrical connector.
- Replace the dust cap, test the headlights, and reassemble any components you removed.
Note: Avoid touching the glass of the new bulb with bare hands; oils from skin can shorten bulb life. Use gloves or a clean cloth when handling the bulb.
Notes on accuracy and variability
Variations by market
Headlight configurations can vary by market, trim level, and even production run. While H4/9003 is typical for many US-spec 2005 Altimas, some regions may have different assemblies. Always confirm the exact bulb size by checking your vehicle’s manual, the bulb itself, or the existing bulb base before purchasing replacements.
Summary
In most 2005 Nissan Altima models, the high-beam function uses an H4 dual-filament bulb (also referred to as 9003). For replacement, use a like-for-like H4/9003 bulb and follow standard replacement steps to ensure proper fit and alignment. If in doubt, consult the owner’s manual or a Nissan service professional.