kittykaTT

Recently noticed haze building inside the front right headlamp unit of the MkII TT. It's a November 2006 build. Brought it to the dealer and been told that "it is due to headlamp circulation which allows air from the outside to flow through headlamps. This will not effect (sic) headlamp function."

photo---

http://www.flickr.com/photos/21595634@N05/2522837896/

Im choosing not to debate with the dealer and have instead brought it to the attention of Audi Australia.

Has anyone else encountered this?

JeffreyTT

The lamps are open to the outside environment. As the lights heat/cool, moisture will condense on the inside of the lens, but will evaporate as temps increase or after the lights have been on for a bit.

ht606

If that is the case, then why only the right lamp and not both?

JeffreyTT

TSB 94 08 03 2012749/5 Jan. 28, 2008

Condition
Condensation is visible on the inside of the headlight, taillight, fog light, side marker light, front turn signal, daytime running lights, or third brake light lens.

Technical Background
Damp air settles on the inside of a cold lens, which creates condensation.

The headlight circulation system allows air from the outside to flow through the headlights. This open waterprotected ventilation system (needed for pressure compensation) creates different climate zones in the headlight: very warm areas, where the lens is warmed up by the light, and relatively cool areas, where the lens is cooled down by the air flow.

Considerable differences in humidity and temperature between the inside and the outside of the headlights, even while driving, can lead to condensation. This is especially true in cold and wet weather, but it can also happen after a car wash, after steam cleaning the engine or the front end, with overnight temperature changes, etc. This phenomenon is more visible on lenses made of clear glass than on lenses with patterns. The moisture doesn't affect the headlight function (light performance) and doesn't lead to corrosion or other damage to headlight parts.

Service
For headlights, the affected lens surface should be clear after approximately 10 minutes of light operation, although the entire lens surface may not clear. The clearing process depends on the outside temperature and the humidity.

In cases where water droplets have formed on the inside of the lens or water has collected at the bottom of the light assembly, check for leaking seals and/or cracks in the lens or light assembly. If no damage is found, use compressed air (less than 30 PSI) to clear the lens.

On light assemblies with LED lights, e.g. S6 daytime running lights, the LED lights do not emit enough heat to clear the moisture from the lens. Only the pressure difference of the ventilation system provides the air flow to clear the moisture on the inside of the lens. The design of the ventilation system on these types of lights will ensure the lens is clear after a few miles have been driven.

Do not replace light or lens assemblies for these conditions.

kittykaTT

That's what im thinking ht606. if air is supposed to circulate, the "haze" should be on both headlight units.

Thanks JeffreyTT, but its not water condensate or moisture, its haze "burnt" into the inner surface. It doesn't go away even after running the headlights after 15 minutes.