Hi there folks! First of all this is my first post on this forum so I thought I would say hello before I ask a question. I'm a new Audi owner (2000 4.2L)---previously being a life-long Saab owner. I think I recognise a few folks on this site from Saabnet!

The 4.2 is a beautiful ride. Being a Rolls Royce tech (RB211 jet), I have been under the hood far more than I need on this baby. I have the VAG-COM and shop manuals, so I'm ready;-)

So here comes my question. I had my headlight(s) vandalised a couple weeks ago, so I found 2 very nice used headlight assemblies from a 2003 A6 4.2. Little did I realise the Xenon lens diameter is larger than my 2000's. I did some research here and came to realise that the larger lense is a bi-xenon setup (from 2002-?), With this being my firts Xenon equipped car, I need a little clarification....do I need to change the wiring harness from my 2000 xenons to work the 2003 bi-xenons, or are they plug and play?

thanks for reading

Steve

 

Good question. The 2002+ is brighter with a larger lens. Perhaps wiring differences for bi-xenon.

 

huh, intersting. The plug looks the same with (I believe) the same number of pins. Maybe that is all it is? It still has the halogen hi-beams, so maybe I'm confusing some of the archived info I read...

 

Good, if they match. I just don't know about current draw. Maybe the same?

 

The only info I have found on current draw is 35W for xenon bulbs. I'll see if the manuals have specific info on that...if there is a different wattage for the larger lense.

If anybody with a 2003/2004 4.2 is reading this, do you have bi-xenon? It's tough sifting for accurate info on the net.

 

It think the only functional difference is that the cutoff shutter on the newer Xenon low beam is moved out of the way for high beam operation. I don't know if that is activated from within the Xenon assembly when the high beam is activated or if that signal comes in on a wire independent of the high beam.

 

Two totally different Audi's, but I think my 2000 4.2 with "single" xenon (not bixenon) probably has the brighter highs overall than my 2006 A8 from direct observation and driven relatively back to back. A8 is bixenon with adaptive lighting as well. Reason is pretty simple. In bi xenon the focal mechanism mechanically shifts to get the light further out. But it's the same bulb underneath as I recall, albeit HID. That's probably the key point--there is no wattage step up to bixenon, but rather as I understand it just stays HID in the high beam position. AFAIK, there aren't two xenon bulbs buried in there or some such. Meanwhile, the 4.2 has the dedicated high beam bulb (at higher, albeit halogen wattage) and reflector on a 2000, all optically optimized for that high beam throw. And street high beams in halogen already get a 10W advantage over lows (65 vs. 55 at stock). I know HID's have more effective light by a good margin against halogen lows, but halogen highs get another 10W head start. Oh yeah, and if you either step up the wattage a bit--no, not to 100W either--or you learn the trick of holding in the stalk when you temporarily want to kick in both highs and lows to get more light out there, the 2000 out performs the 2006, particularly now with the dual frequencies of HID and halogen. If I were looking to mod this for major lighting, it would be using relays to get the halogens and the HID's on together w/out holding in the stalk. That would pump out more light than the bixenon's by a wide margin--it clearly does when you pull the stalk in and light 'em both up.

I still take the 2006 over the 2000 on front lighting, but that's due to adaptive corner control and way, way better fog lights, not general front lighting performance.

If I was looking at anything here, I would probably focus on low beam performance--is the overall low beam apparent brightness better in the 2002+'s. That won't be a bulb or bixenon related question, but rather a question of optics design of how well it throws the light where best used. And yes, the 2006 A8 maybe gets the nod here some, but it's close and I think it's really the adaptive that makes the difference. I have no back to back data on A6 pre and post bi xenon though.

 

If I'm correct the difference in bixenon is just the mechanical optics movement in the HID element, then the bulb is always the same on the HID side. But there will be wiring differences where it needs a high beam signal from somewhere to kick in the (relay fired?) motor to shift the element. For wattage draw on high, I expect it's lower, 65W halogen goes away, with 42W (?) HID just staying powered like it does in low beam mode. Optics movement motor draw is momentary (fraction of a second) and I expect not very big.

 

thanks for the info. To add to this the ballast P/N is the same for both the older xenons, and the 2003's. Me being the xenon master (yeah right!)....this tells me nothing Well, it won't hurt to try. I have on here, and am awaiting the other probably next week...so I'll let you guys know.

cheers

steve

 

after further investigation i found 2 extra wires--brn/wht going from the halogen beam to a module at the bottom of the xenon lens. This may be for turning off the halogen when the xenon function or even to activate the shutter as these two wires are in sewries to the brn/wht wires that go to the harness, and t ehn to the signal stock in the car. BUT I'm sort od speculating here...and I'm probably going off on a tangent that may not need to be explored;-) At the very worst I can swap all the internals and reflector to the new housing and lens...as my lenses are the only thing shattered.

As well the bulbs are the same