Condensation in my headlight!

[hockeyman474]

My new to me C5 S6 has condensation in the passenger headlight after we got steady rain for a few hours the other day

Who has baked their C5 headlights before?

I have never done it so I would be more comfortable using a box/hair dryer method to get the moisture out and then apply a bead of outdoor/heat resistant silicon around the seam.

Anyone with experience baking Audi headlights, should I be scared to do it or should I just go ahead and do it? I know that would be the better fix but I am obviously apprehensive to bake a vital part of my car that I haven't even had for a week. From what I have been reading, it seems about 200* for 10-12 minutes and then resealing with butyl tape/glue.

Any advice would be greatly appreciated!

[SteelyS6]

I have done it several times, I would say it takes even less time, 5 to 8 mins. Cleaning the Butyl out is a task. Also check the housing for cracks and the seal around the back cover.

Reseal with Butyl.

Currently in the process of taking two allroad headlights to make one good one.

[rollerton]

Sucks and it could be a chronic problem. I get some condensation in ONE of mine also but the lens is sealed perfect. If it fogged slightly up just sitting there after driving then I'd guess it might be the back door not seated or sealed as well as it could be. If it's pretty bad then doing the lens right off can save you some hassle. From my experience C5 lenses come off pretty easily; on a hot summer day leaving the housing sitting in the hot sun for 15-20 minutes is enough to soften the seal and pull the lens off. Then I use a screwdriver blade (heat it up intermittently with my little torch) to scrape the old sealer out of the channel in the housing. The oven works too, but careful on the temp, 200* is probably right.
I've had good luck when it's fogged up popping the back door off and running a hairdryer on warm to dry out the moisture; the fogging problem in mine is oddly intermittent.

[m_haiser]

when I did mine I did 200 for 5-7 minutes and still had to pull pretty hard to get them apart. just remember to pull out all the bulbs first

[Daft]

For something to laugh at, here's the answer Audi provided long ago to mitigate the headlight moisture buildup:







10 minutes eh? Sure...

[hockeyman474]

If it fogged slightly up just sitting there after driving then I'd guess it might be the back door not seated or sealed as well as it could be. If it's pretty bad then doing the lens right off can save you some hassle. From my experience C5 lenses come off pretty easily; on a hot summer day leaving the housing sitting in the hot sun for 15-20 minutes is enough to soften the seal and pull the lens off. Then I use a screwdriver blade (heat it up intermittently with my little torch) to scrape the old sealer out of the channel in the housing. The oven works too, but careful on the temp, 200* is probably right.
I've had good luck when it's fogged up popping the back door off and running a hairdryer on warm to dry out the moisture; the fogging problem in mine is oddly intermittent.

The one major thing I dislike about this forum is the photo uploads. Basically mine is pretty bad. It rained steady for hours and I came out to in the next morning all watered over on the inside. I may just take both of them off, clean the front, reseal the passenger size and replace the corner lights that have seen better days.

I may try just setting it in the sun this weekend as it is supposed to be upper 80s. If that doesn't work, oven at 200* for 5-8 minutes it is.

[hockeyman474]

For something to laugh at, here's the answer Audi provided long ago to mitigate the headlight moisture buildup:







10 minutes eh? Sure...

HAH! This issue popped up Wednesday. I drove home from work - 45 minutes - with the lights on and there was still 50% in there when I got home.

[PaperToast]

yeeea, gonna be one of those things that we all deal with
mine fogs sometimes after i wash it, but it goes away
but i live in a very low humidity location, <20% most of the year

[mithril]

If you’re going to fix it, do it right: http://www.audizine.com/forum/showth...lft-headlights

I can’t recommend the Philips 85122 XV2 bulbs enough, they’re pricey but amazing.

[hockeyman474]

If you’re going to fix it, do it right: http://www.audizine.com/forum/showth...lft-headlights

I can’t recommend the Philips 85122 XV2 bulbs enough, they’re pricey but amazing.

The bulbs themselves are fine for now, just need to get the condensation out. Not looking to do a complete overhaul on the lights.

Sadly, the link you posted, most of those links are inactive now.

[chris86vw]

I soaked one of mine myself the other day.. such an idiot.

I had some corrosion on the connector causing a level adjuster fault so sprayed connecter with battery terminal cleaner. You need to rinse it off to stop the cleaning and I wasn't thinking and did it with the back cover off.. I'm probably pulling it to spray electric tape that harness before a trip but for the past few days can't help but shake my head every time I walk up to the car.

I rebuilt my driver side with the fx-r 3.0 2.5" world of a difference but both harnesses are toast so not wasting time with passenger side. Going to pickup some of the Halo allroad lights and fingers crossed I can swap in the stock allroad internals to keep the stock look.


Torn between the cbb and the xv2 for bulbs. Similar output but cbb slightly bluer white.

[mithril]

The bulbs themselves are fine for now, just need to get the condensation out. Not looking to do a complete overhaul on the lights.

Sadly, the link you posted, most of those links are inactive now.

Fixed the links, apparently TRS has updated their website in the 5 years since I wrote that howto

In order to prevent recurrence of the condensation you're going to have to reseal the lights which requires baking them open to replace the sealant. If since you're doing 90% of the work by opening the lights to reseal them you might as well also upgrade the projectors while you're in there. Changing the bulbs can be done at any time, I suggest it only because if you don't know the age of the bulbs they probably need to be done. HID bulbs have an effective lifespan of about 2000hrs which converts to about 4 years for most people, after that 2000hr mark is reached the bulbs still light up but are only producing 30 - 40% of their normal lumen output. In every case where I've bought a used vehicle with HID the bulbs have been no better than halogen because most people seem to think that HID is a "lifetime" bulb.... just like VAG transmissions get a "lifetime fill"

[hockeyman474]

Fixed the links, apparently TRS has updated their website in the 5 years since I wrote that howto

In order to prevent recurrence of the condensation you're going to have to reseal the lights which requires baking them open to replace the sealant. If since you're doing 90% of the work by opening the lights to reseal them you might as well also upgrade the projectors while you're in there. Changing the bulbs can be done at any time, I suggest it only because if you don't know the age of the bulbs they probably need to be done. HID bulbs have an effective lifespan of about 2000hrs which converts to about 4 years for most people, after that 2000hr mark is reached the bulbs still light up but are only producing 30 - 40% of their normal lumen output. In every case where I've bought a used vehicle with HID the bulbs have been no better than halogen because most people seem to think that HID is a "lifetime" bulb.... just like VAG transmissions get a "lifetime fill"

I just don't feel comfortable enough replacing the entire unit, even with your detailed post. Maybe I can see if a friend can do it for me. He does that sort of thing all the time.

[chris86vw]

HID bulbs have an effective lifespan of about 2000hrs which converts to about 4 years for most people, after that 2000hr mark is reached the bulbs still light up but are only producing 30 - 40% of their normal lumen output. In every case where I've bought a used vehicle with HID the bulbs have been no better than halogen because most people seem to think that HID is a "lifetime" bulb.... just like VAG transmissions get a "lifetime fill"

My TT had 220k or so on it when I got it and 99% sure the original bulbs!!! The first time I drove it at night rural no street lights, blind hills and curvy roads.. I was scared, like called the GF to tell her if I wasn't home in 20 minutes head towards my work to find where I drove into a ditch. The parking lights were outshining the actual headlights!

The fact that these were marketed (and still are) as lifetime is just ridiculous it has made so many people believe that they only need to be replaced if they fail and that simply is not the case.



Threw some morimoto bulbs in it since it is just a beater about 2 year ago.. and I think have only driven it at nice only once or twice since, great investment :)

[hockeyman474]

My TT had 220k or so on it when I got it and 99% sure the original bulbs!!! The first time I drove it at night rural no street lights, blind hills and curvy roads.. I was scared, like called the GF to tell her if I wasn't home in 20 minutes head towards my work to find where I drove into a ditch. The parking lights were outshining the actual headlights!

The fact that these were marketed (and still are) as lifetime is just ridiculous it has made so many people believe that they only need to be replaced if they fail and that simply is not the case.



Threw some morimoto bulbs in it since it is just a beater about 2 year ago.. and I think have only driven it at nice only once or twice since, great investment :)

I guess the first thing I should do is drive this car at night! Thankfully it's summer so I haven't needed to in the 6 days of ownership but I'll test it out tonight.

[mithril]

My TT had 220k or so on it when I got it and 99% sure the original bulbs!!! The first time I drove it at night rural no street lights, blind hills and curvy roads.. I was scared, like called the GF to tell her if I wasn't home in 20 minutes head towards my work to find where I drove into a ditch. The parking lights were outshining the actual headlights!

Yup, same deal when I bought the Touareg w/ 165,000 km back in February. The H7's used as the AFS cornering lights threw more light than the projectors. The light on the passenger side especially was so bad I was fully expecting all the chroming to have baked off the projector bowls. Initially swapped in some Morimoto XB's because they were cheap and while that proved that the issue was the old bulbs and not the projectors (thankfully!) I wasn't happy with the colour temp, way too blue. One the bulb had a broken connector pin so I got TRS to give me an RMA and credit towards the Phillips XV2's I should have bought in the first place. Had both the 85122+'s and original XV's in my S6 which was an incremental improvement. The XV2's are another incremental improvement over the XV's. I prefer the 4800K range as it's close to OEM, lights up the road without the light itself being noticeable if that makes sense.

I just don't feel comfortable enough replacing the entire unit, even with your detailed post. Maybe I can see if a friend can do it for me. He does that sort of thing all the time.

Fair enough, but honestly the hardest part is actually removing the headlights if you choose to do that without first removing the bumper. You may also find that you can't ever fully get rid of occasional light condensation, especially in humidity. I found that condensation was worse in the winter here in the PNW but I know Detroit is ridiculously humid in the summer (I'm originally from Windsor) so you may always fight it a little bit on temp changes.

[Grainreaper]

My left headlight is always getting condensation in it, I need to bake and peel the lenses and re seal them, in the meantime I have a small hole at the bottom of the housing to vent them a bit, it has greatly reduced the severity of the fogging from lots of droplets inside to just a bit of fog that buttons away in short order. I've been looking for the back cover gasket but so far no luck finding them anywhere

[chris86vw]

Actually noticed mine cleared up. I drove 5 hours then 4 hours Saturday (fun day) lights on for about 80% of it. Before I left I cracked the back cover open and now it is completely dried out.

[Terry.Reese]

mine was due to my seal on the back not being clicked all the way shut, let just enough moisture in to be a hassle. pulled it off, cleaned it and dried it with hair dryer blowing in, closed it back up and no more moisture, been 3 months now, clear.

[hockeyman474]

mine was due to my seal on the back not being clicked all the way shut, let just enough moisture in to be a hassle. pulled it off, cleaned it and dried it with hair dryer blowing in, closed it back up and no more moisture, been 3 months now, clear.

Maybe I should try that easier part first....it has rained decent the past 2 out of 3 days and there is zero evidence of moisture this time.

[JMURiz]

Sounds similar to my car...sometimes I get water issues in the cabin and headlights, other times nothing. I may try the seal trick Terry mentioned above, when I polish my lenses.

[hockeyman474]

mine was due to my seal on the back not being clicked all the way shut, let just enough moisture in to be a hassle. pulled it off, cleaned it and dried it with hair dryer blowing in, closed it back up and no more moisture, been 3 months now, clear.

I have been super busy and have yet to take out the headlight but I am wondering it it simply was one of the rear seals. We have gotten more rain in the past week and I have yet to see a drop in there. It's only happened once.

[V1nny]

I resealed my Allroad headlights 3 times, flipped rubber gaskets inside out on the back cover for better seal, inspected both headlights under microscope for any other reasons to leak, and 0 improvement: there is water in them after every car war. Just give up...

[hockeyman474]

I resealed my Allroad headlights 3 times, flipped rubber gaskets inside out on the back cover for better seal, inspected both headlights under microscope for any other reasons to leak, and 0 improvement: there is water in them after every car war. Just give up...

Well that doesn't sound like a fun time.

[V1nny]

Possibly reason they cannot be sealed, is the air expansion and contraction due to cooling/heating. More so with halogen, less with HID/LED, but even these generate enough heat.
few people told me to just drill holes in the bottom, to drain the water

[hockeyman474]

Possibly reason they cannot be sealed, is the air expansion and contraction due to cooling/heating. More so with halogen, less with HID/LED, but even these generate enough heat.
few people told me to just drill holes in the bottom, to drain the water

Mine wasn't showing a visible fill, just condensation.

[V1nny]

I never saw actual standing water inside, so not drilling holes yet

[8520]

I pulled a set of a6 lights apart once with no baking and no heat gun without issue. Removed the clips. Pried a bit with a metal panel removal tool and they came right apart.

Be thankful c5 headlights are butyl. My touareg lights are permaseal and are the devil.

[mithril]

Have you tried cracking apart the Touareg lights Dre? The inside of my lenses could use a clean but if seems a bit much to take aparent permaseal for that reason alone. TRS has a permaseal releasing agent which is supposed to make it a bit easier.

[8520]

Have you tried cracking apart the Touareg lights Dre? The inside of my lenses could use a clean but if seems a bit much to take aparent permaseal for that reason alone. TRS has a permaseal releasing agent which is supposed to make it a bit easier.

Yes. I tried. After getting frustrated and giving up on the perma, I ended up cutting out "panels" from the stock headlight top in order to swap in the MD2S 4.0 projector, and sealed the panels back together with gorilla tape. Believe it or not, we've had zero condensation issues. Treg is garaged 95% of the time, so I'm sure that helps.

[hockeyman474]

It came back :(

Went on a 750 mile road trip the last 4 days. We got torrential downpour 3 times on the trip with no moisture in the headlights. When I got home, I took it through a brand new touchless carwash by my house and when I got home I noticed a fine mist in the headlights. It gone already but looks like I have some more investigating to do.

[V1nny]

It came back :(

Went on a 750 mile road trip the last 4 days. We got torrential downpour 3 times on the trip with no moisture in the headlights. When I got home, I took it through a brand new touchless carwash by my house and when I got home I noticed a fine mist in the headlights. It gone already but looks like I have some more investigating to do.

check 4 little breather valves on the back of each headlight. They are essentially holes with a tiny piece of curved molded hose attached to every hole. If hose is is lost or rotated, water may not get in when raining, but will get in carwash.

[hockeyman474]

check 4 little breather valves on the back of each headlight. They are essentially holes with a tiny piece of curved molded hose attached to every hole. If hose is is lost or rotated, water may not get in when raining, but will get in carwash.

Thanks! I'll check it out this weekend. Of course it's on the harder to reach passenger side. Which direction should they be pointing towards?

[hockeyman474]

check 4 little breather valves on the back of each headlight. They are essentially holes with a tiny piece of curved molded hose attached to every hole. If hose is is lost or rotated, water may not get in when raining, but will get in carwash.

Got a ton of rain again last night, this time it actually snuck into the headlight.....I can't win!

[hockeyman474]

Anyone ever put LED foglight bulbs in a C5? Any good brand/source to get them?

[julex]

Got a ton of rain again last night, this time it actually snuck into the headlight.....I can't win!

Down of course so that they can gravity drain. If you have them pointing anywhere outside of bottom 180degree arc, they will collect water and never be able to drain it.

[julex]

I pulled a set of a6 lights apart once with no baking and no heat gun without issue. Removed the clips. Pried a bit with a metal panel removal tool and they came right apart.

Be thankful c5 headlights are butyl. My touareg lights are permaseal and are the devil.

My 01 allroad headlights were permasealed from factory. yay.

[Fahrvergnugen]

Drill a TINY hole into the side of the assembly, just through the front lens. This TINY hole, say 5/64 or smaller, is not big enough to allow any large amount of water in, and when driving, it will evacuate the moisture more than it is now. Did this to mine and it helped, but didn't ever go away completely. Do it down low, as far back as possible and still drilling into the cavity, not the edge.