How bright are your xenons?

[eveeyeda]

There's a little known problem with xenon lights that over a period of time the projector lens (that focusses your light output) clouds over with a milky film which causes the lens to perform below its intended design. Think of it like a breathing on a camera lens beore taking a picture - yes you can make out the subject but nothing is in focus. This degradation is a very slow process so not many owners will notice the difference but if like me you've driven a lot of cars you know what a good headlight system should perform like especially in a premium brand. This issue is not confined to just one manufacturer and VOSA the MOT body is aware of the problem but MOT stations do not measure light output against new specifications so they won't fail a car with this issue which is strange considering that if you had severe rust on the reflector of an ordinary halogen headlight you'd probably get a failure notice. How do you know if your car has this problem? With the headlights switched off (or you will damage your eyes!) look into the projector lens and see if you can make out what's behind it (some cars have what they call a fresnel lens fitted (look like indicator lights) - on these you can't do this simple test) but if you're car is fitted with a glass lens you should be able to carry out this simple test. If everything is opaque then that's how much light is being prevented from being focussed into a beam. Audi claim that factory fitted xenons should be twice as bright as halogens (when new) so how good do you think your xenon lights are even on cars less than five years old? With modern headlights costing thousands (mine including fitting about £2K) it's also a good idea to check out the xenon lights on any car you may be buying because it's likely that no warranty will cover the replacement that's of course if you can convince the dealer (two visits in my case)that the problem exists which thankfully they did in my case.

[y2blade]

I'm not reading that!

Do you not have an "Enter" key?

[zeduffman]

Mine are really fking bright, thank you.

[kazste]

They make nightime into daytime so I'm happy.

[DaveCWK]

Where does this film which is deposited on the lense originate from?

[Defcon5]

The ones on my Lupo GTI were fantastic

[Jimmy No Hands]

The ones on my Z4 were a bit poor. And the self leveling decided to stop working a few times.

[eveeyeda]

It's a natural occurence but the general consesus is heat coming off the bulbs attracting dust etc.

Here's a link to illustrate the problem and apart from buying new headlamps the work involved in getting rid of the film build up.

To those who have legally fitted bi-xenons I'm pleased you've got super bright lights but there are many out there who are unaware of what a good bi-xenon ouput should be like and it's to those I suggest they inspect their own cars.

http://www.clublexus.com/forums/sc-400-300/183023-...