Why are my wife's Bix different from mine?
I just got some depos and they make a huge difference. I think I need to aim them though. They don't have a cut off at all and it's irritating. Maybe someone can tell me how to adjust them to get a cutoff if that's possible

I just got some depos and they make a huge difference. I think I need to aim them though. They don't have a cut off at all and it's irritating. Maybe someone can tell me how to adjust them to get a cutoff if that's possible
They were Bi xenons I ordered off ebay and installed myself. They are nice except I wish it had that nice cutoff that his picture showed in the descripition.

EDIT: And define Bi Xenon headlamps. 2 (Bi) functions from one projector. Dipped & main beam.
Last edited by Glyn M Ruck; Jun 12, 2012 at 07:14 PM.

This might lend some credence to the comment that Depo has mounted some projectors upside down although I find it hard to believe.

Thanks for the picture, Glyn. That helps me understand what is (or is supposed) going on.
The Best of Mercedes & AMG


Jim - This is boggling. Glyn is right if it fires up and maintains output the ballasts should be fine. The bulbs would shut off or flicker if they weren't receiving the correct power supply. It won't hurt to swap one of her bulbs with one of yours to see what happens. Maybe these bulbs have a problem and you need new ones? If that is the case I recommened Philips.


Jim - This is boggling. Glyn is right if it fires up and maintains output the ballasts should be fine. The bulbs would shut off or flicker if they weren't receiving the correct power supply. It won't hurt to swap one of her bulbs with one of yours to see what happens. Maybe these bulbs have a problem and you need new ones? If that is the case I recommened Philips.
Last edited by Glyn M Ruck; Jun 13, 2012 at 09:06 PM.


I think without over analysing this issue you should take a known bulb from your car & install it in your wife's vehicle.
It is a tight fit for sure but it shouldn't ultimately be anymore difficult than changing a normal bulb. That all being said let me know how it works out because I intend to replace the bulbs that came in mine with genuine Phillips D2S bulbs. My light output is very clean and consistent right now but I'm sure with Phillips bulbs it would be even better. Plus I'm sick of 6000k.. tooooo blue. Makes the IS350 and 135i bixenons look like halogens.

It is a tight fit for sure but it shouldn't ultimately be anymore difficult than changing a normal bulb. That all being said let me know how it works out because I intend to replace the bulbs that came in mine with genuine Phillips D2S bulbs. My light output is very clean and consistent right now but I'm sure with Phillips bulbs it would be even better. Plus I'm sick of 6000k.. tooooo blue. Makes the IS350 and 135i bixenons look like halogens.
BTW, I got a response from Simon.
I told him that my wife was initially pleased but then they started to dim and she said they are getting worse. I asked him if he could inform me of the terms of the warranty. Simon asked back what I meant by "getting worse"!
When I told him that worse = dimmer and that they were not as bright as the OEM halogens, he asked if that was with both sides or just one.
I told him it was with both but I haven't heard back. Not very confidence inspiring, but then maybe he's studying up on electrical engineering and optical refraction, or maybe he's busy in a shop deconstructing the housing, bulbs, and ballast to fully understand the potential causes. Or, maybe he just hasn't had time to write back...


Or maybe I just over analyse everything. It's in my nature to do so I'm afraid. I have to fully understand things
I should say that even if you get new bulbs and that fixes the problem, the alignment screws are detached now and you'll never be able to align them. So either way those lights are screwed up. Sorry to be the bearer of bad news..


The elevation screws (actually only one is possibly screwed up) is an issue I've thought about. I took a look at an OEM light and assuming the mechanism is similar, it should be repairable. Now whether it is worth the time to hassle with that vs a new one - that is another question. It might be a question of a long screwdriver and judicious poking and prying and it might be that the thing has to be taken apart. We'll see, but first is to swap bulbs and see what happens. Probably tonight. I'll keep you all posted.
Update: So far I still haven't heard back from Simon (fishcake). I have only to assume that he is having trouble with the big words in the electrical engineering or optical refraction texts. Maybe he's digesting my answers (getting worse means getting dimmer and both not one light is dim). But then, it could be that he started his summer vacation (on the Riviera or Bahamas, maybe) before he got my last email. I might be too hard on him, but if he doesn't know, he can say that...
Last edited by ncmudbug; Jun 15, 2012 at 08:24 PM. Reason: update

One of my bad habits is to try to analyze a problem before investigating it. I'll think, wonder, ponder, ask others (this thread), etc. before I start getting my hands dirty. The problem was that the bulbs were not securely installed in the housing and projector. I first looked at the driver's side light and the back door that seals the light from the elements was ajar and when I looked in there, the black plastic ring that locks the bulb in the housing was not engaged (it's a bayonet type latch). It was just flopping in the breeze. I went to the passenger side and it's door was closed but it's bulb was flapping, too (remember that kids, the driver's side always flops and the passenger side always flaps... or is it the other ways around?)! So Glyn, you were right yet again!!!
It's a tight squeeze and I had to figure out how it was all supposed to go together, but with a little fiddling, I got them all back in securely (I hope) and they seem to work.
For those who are interested, the bulbs fit only one way. The external "wire" points down. You pretty much just place the bulb in the housing. It is not secured till you put the retaining ring in so you need to be a little careful (well you need to be a little careful all the time because I imagine you want to make sure you don't touch the bulb with your fingers). There is a tab on the retaining ring and it is at about 5 o' clock if you are looking forward behind the housings. Once that is seated, a slight turn clockwise locks it all in place. Then you attach the pug on the back of the bulb and it too is a bayonet latch. The door just requires fiddling. The "hinge" part are hooks that go in little holes - you can see them when you're putting it back in so just align it the best you can and play with it till it can be latched.
A long time ago, I promised Matt a picture of how they secured my ballasts in the engine compartment. I can still do it if you want, but it was a trivial matter of using double stick 3M badge tape and sticking them to the wheel arches.
I suspect that when Simon replaced the bulbs with the 6000K ones, he didn't fully seat the ring and as the car drove around, they shook loose. Thus Mrs. NCMudbug liked them at first but then they got worse - maybe at an accelerating pace as they got further and further away from where they were supposed to be. The next worry is the alignment. In the garage, it didn't look too bad, but we'll just have to see. Now that I know what happened, I realize why it wouldn't adjust!
Thanks, all of you for your helpful and supportive suggestions and comments.

The position of the arc is CRUCIAL as stated & illustrated.







