Open the catalog for almost any recent vehicle and you will find two or three different headlamp assemblies for the same model year. They look alike in a photo. They are not interchangeable. The difference is the light source the car was built with, and it usually follows the trim level.
Tell them apart on the car
- Halogen. Warm, slightly yellow light that comes on at full brightness. The bulb twists out of the back of the housing and has a visible filament. Common bulb names are H11, 9005 and 9006.
- HID, also called xenon. Cool white light that flickers bluish for a second or two as it starts, then steadies. The low beam usually sits behind a projector lens. The bulb name starts with D, such as D2S or D3S, and there is a metal ballast box on or under the housing.
- LED. Crisp white light that is instantly on, usually from several small emitters or a row of lenses. On most cars there is no bulb to remove: the light source is part of the lamp.
Not sure? Switch the low beams on and take a photo from the front, then one of the back of the housing. Either of those, or the VIN, answers it.
Why they do not swap
Each type has its own wiring connector and its own electronics. An HID lamp needs a ballast. An LED lamp needs a driver module. The car’s body computer is set up for the lamps it was built with. Installing a different type means changing wiring and modules, and sometimes programming, not just the lamp. Order what the car had.
Other things that change the part
- Adaptive and self-leveling lamps. Lamps that turn with the steering or level themselves carry extra motors and plugs.
- Bezel color. The inside of the housing is chrome on some trims and black on others.
- Build date. A mid-cycle refresh often changes the lamps. The label in the driver’s door jamb gives the month and year the car was built.
What comes in the box
A replacement assembly is normally the housing, lens and reflector or projector. Bulbs, ballasts and control modules are usually not included, and you transfer yours from the old lamp. Your quote says whether they are included.
HID systems run at high voltage. Disconnect the battery before you unplug a ballast, or leave that job to a technician.
After it is on the car
Aim it. A new headlamp sits a little differently from the one it replaces, and a lamp pointing a degree too high blinds oncoming drivers. Most shops aim lamps in a few minutes.
Look for DOT molded into the lens. It is the manufacturer’s own certification that the headlamp meets the federal lighting standard for road use. The SAE letters beside it list the functions the lamp performs.
Ordering
Request a part with the VIN and tell us what the car has now. See Lighting for the full list of lamps we sell.