what type of HID bulbs are used? not as a kelvin scale but are they H4 or H1? D2r? and where are the highbeams? is it on one bulb?

 

Don't know what bulbs are used but the high and low beams are the generated from the same bulb.

 

neither H1 nor H2... it's probably a D2S bulb.

 

I don't know what type of bulb 04TL is using. But it's the only one bulb there.

Acura said:

Previously, the TL had HID (High-Intensity Discharge) low beams coupled with conventional halogen high beams. The new TL headlights feature HID high and low beams, as well as built-in fog lamps. These bi-function HID high/low beams are made possible by a shutter device that mechanically controls the light output of the HID unit. When the driver selects high beam, an electric solenoid in the headlight moves a shutter forward, opening up a greater reflector area inside the headlight. When the lights are operated on low beam, this shutter repositions to act as a cut-off to keep the lighted area closer to the vehicle.

 

Wow! So, it sounds like when the headlight blows you'll lose both the High & Low beams at the same time.

That would suck if we didn't have headlights bulbs that never burn out.

On a more practical note, when the headlights are in "Low" mode the shutter will be reflecting heat back into the headlight area - which will lower the expected lifetime of the bulb. You will actually extend the lifetime of your bulb by using the "High" setting as much as possible. I kinda like that.

 

HID bulbs are rated 3000 hours. for most people, that is about 100,000 miles. that is unless you plan to only drive your car at night and never during the day time.

bi-xenon projectors have been around for a number of years now. it's no different than regular low-beam HID projectors, other than the fact the shutter can be moved to allow more light upwards and hence becoming high-beam.

a strictly low-beam HID projector has a static shield (as with a halogen projector). it's the nature of its design to create that horizontal cut-off. heat isn't an issue because HID bulbs do not have filaments. the light is generated by igniting gasses and a mixture of salt crystals. due to the lack of a filament, most of the energy is not wasted as radiated heat (as in conventional halogen bulbs).

 

With oem hid, there are only two types of bulb, D2r(reflector) and D2s(projector). The 04TL has projector lights, so it should be D2s.

 

usc - Thanks for the useful information!

I thought that the shutter was part of the car, not the bulb. Am I mistaken?

If it's part of the bulb, how expensive are replacements?

 

the shutter is just an internal shield of the projector headlamp. if you hold a projector sideways, from "front-to-back":

- round convex lens
- metal shield (or shutter for bi-xenons)
- bulb (d2s)
- round bowl-shaped reflector

for non-bi-xenon projectors, the shield/shutter doesn't move. for bi-xenon projectors, the shutter has a solenoid connected to it that will move the shutter downward to allow more light to exit forward from the reflector.

the part that may fail earlier would be the solenoid. should the bulb fail, it's a simple bulb replacement. if the solenoid fails, it would theoretically be locked at the low-beam position. and in order to fix it, you'll have to replace the entire headlamp.

 

usc, thanks a lot.