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      05-27-2012, 07:19 PM   #9

Drives: '07 328i 6MTsp / '11 535xi 8AT
Join Date: May 2012
Location: Oakville, Ontario

iTrader: (0)

Originally Posted by *******_ View Post
You are actually wrong sir^^

For example LCI non AHL xenons sisnt have high beam as normal h7 bulb but only xenon , just like 911, Audi A4 and many others, new ballasts are prepared po bliknking with xenon without problem. I have lci xenons blink very often to friends or just to beware people of cop patrol and not a problem at all...
Originally Posted by Really?! View Post
If look closely at a LCI vehicle or just about any other newer vehicle that has xenons the low beam, high beam, and flash to pass use the same projector. How is this done?

The LCI vehicles have a shutter built into the projector for the low beam. So the bulb intensity will not change, it is like pulling a shade up on a window to allow more light to pass thru. The xenon without the shutter would not give you the same high beam intensity right away. The shutter can actually be heard if you are right next to the lamp. The fast acting shutter is what makes this possible. The bulb is on at it brightest but the respective module reigns the brightness in with the use of the shutter (aka window shade)
So without having the shutter mechanism built into the lamp you are not going to get the same results. So even coding is not really a solution without replacing the lamp assembly for a LCI lamp assembly and then coding. Hope this sheds some light.
I have a pre-LCI E90 and it has bi-Xenons. It has the shutter, and uses Xenon for low and high beam. It also uses the halogens in the assembly at half-brightness for DRLs.

If the headlights (i.e. Xenon low beams) are off, it will flash the halogen DRLs at full intensity if you pull the stock. If the xenon low beams are on, it will still flash the halogens if you pull the stock. If you push the stock, then it will flip the metal shutter in the Xenons to open up the full beam for high beams.

If the headlights are on, this is where you can code the car to use the shutters for flash-to-pass instead of using the halogens.

If the headlights are NOT already on (which is the case I've been discussing) you would have the fire the Xenons from dead cold and off in order to "flash to pass" using Xenons in the daytime.

I think this is bad for the ballasts, bulbs, and won't work all that well because xenons don't illuminate fully right away. When I turn on my low beams there's not that much light for the first second. Then it spends the next 3-4 seconds turning from blue to white and it's finally up to full brightness after a full 5-10 count from turning them on.

It's my personal opinion (yes, it's just personal opinion) that using xenon "flash to pass" when the xenon lights are not already on is stupid, cosmetic at best, not all that effective, and likely hard on the equipment. Feel free to pay to replace those ballasts and bulbs early just to look 0.01% "cooler".... Xenon "flash to pass" when the xenons are already on (which is BMW's factory operation when coded for this) is not any harder on the ballasts and lamps, will be effective (because the Xenon bulbs are already fired) and is just a case of user preference or possibly law in some jurisdictions.

Just to see how well it works, why not just crank your headlight control knob from off to low beam to off to low beam a couple of times per second to simulate a quick "flash to pass" double flash and see how well the Xenons respond to that. This might tell you why BMW didn't allow the car to do that from the factory.