northernmonkey

well its been raining all day just noticed that the little condensation patches in both headlights (xenons) has returned. the patches are on the sides (inside) of each unit near the reflector LED lights.

I had this before and the dealer replaced the complete headlight units, as its now happening again i am wondering is this is just one of them things and this will always happen to some degree in wet weather ?

also there are little patches of condensation in each fog light today to....


...any thoughts?

ISUK

Condensation within Xenons seems to be a natural occurrence. Every car I've had with Xenons has had misting inside the unit when there is moisture in the air. I think it is more to do with the very high heat build up in the light unit. When you switch off your lights and they start to cool, the warm air inside the headlight seems to react to the colder air on the outside and this cause the air trapped inside the light to condense into moisture. As the temperature equalises the condensation dries out and disappears. This has happened to me on an X5, Audi TT and Audi A4 cabrio before my 530d - all had xenons.

What I can't understand is dealers not recognising that this phenomenon cannot be cured as you will always have air trapped within your headlight assembly as it is not a vacuum sealed unit. I guess they just haven't woken up to the fact that these lights get very hot.

Forgot to mention that it also happens on my Z4. Other people on a Z4 forum have complained about the same issue, had their lights changed by the dealer, then had the "problem" re-occur. As I said it seems to a natural result of the intense heat build up and I cannot understand why BMW let dealers continue to swap light units under warranty (if indeed they do - I suspect they just let them dry out then claim they've been changed).

Kiwi530i

Just had my dealer agree to replace my headlights for the condensation problem. Will see what happens with winter coming up.

northernmonkey

ISUK, yes you could be right just been out and checked them and the Xenons have now cleared up on their own, so this could just be "normal" like you say.

there is a bit of condensation still in the fog lights.....might ask dealer to replace them as I have not even used the foglights at all.

ISUK

Northernmonkey,

Misting of foglights is an age old BMW problem. These little round units are the same type as fitted to the 3 series coupe. I had this constant issue with my 2000 model year 323Ci and had the fogs changed under warranty but the problem just came back. The issue with them is that there is a small breather pipe fitted at the rear to dissipate heat. It seems that due to its close proximity to the road it is vulnerable to spray from the front wheels getting into the pipe. This causes the condensation problem. It usually dries out itself as well.

Ed520

i had misting in my fogs as well.....nothing to worry abt, it will just go away

northernmonkey

all lights clear again this morning....well to be fair the Xenons cleared in about 5 minutes last night....fogs took a bit longer but cleared on their own without me actually switching them on at all.

Iceman

I talked to my dealer about it today when I dropped off my car. He told me it is nothing to worry about, as long as there isn't water drops in there. The lights are not totally closed, so that the heat can get out, so a little bit of condensation is OK.

northernmonkey

thanks for this Iceman.

my lights seem totally clear now so I think everyone is right when the climate is really wet/humid, as it has been in the UK all week, then on really bad days it seems normal that after turning off the lights a little condensation patch is ok. pretty sure mine cleared up with 10 minutes of turning off the lights. I will check there is no water in there though to be safe.

thx again.

Iceman

If there is water in there your dealer will replace them. But usually it's just a little condensation. The headlight units are not totally closed because of the heat the lights create. Because they are not completetly closed, condensation can sometimes be seen. As long as it's not water running down on the inside it's nothing to worry about...