Condensation in the tail lights?

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29 August 2008
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RPV, SoCal
Hi, I am seeing a lot of condensation in my tail lights. Even with the weather warming up in the 70-80's in LA, they just don't go away. Anyone knows how to get rid of them and keep them out? Thanks in advance.
 
Thanks for the tip. However, I also get condensation on the back of the trunk lid. When I purchased the car last year, I did see corrosions inside the trunk (on the CD changer bracket, the tool kits). Also, the carpet inside the trunk has some odor.. Anyway, the trunk is empty and dry but the condensation still exist when I pop open the trunk at night... Please help... Thanks...
 
If there is condensation there is moisture in the trunk. The trunk gets hot so any moisture will evaporate and condense in the cooler inside surfaces of the tail lights. Removal the tail lights and replacment the gaskets is a good first step in solving the problem.
 
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Use a blowdryer, and then tighten up the nuts holding them in.:cool:
 
The primary problem is that the gaskets between the taillight assemblies and the body of the car are leaking, allowing moisture to get in when it rains. The water then drains down into the trunk, soaking the trunk mat, which absorbs it and holds it like a sponge. When you drive the car, the heat from the exhaust underneath the trunk warms the floor of the trunk, causing the water to evaporate. When it rises and encounters the cooler trunk lid, it condenses on the bottom of the trunk lid. After you drive the car, when you open the trunk, the trunk lid will be all wet underneath. But the moisture is trapped inside the trunk - it can't completely evaporate out because the trunk seal is holding it in, and there is no opening at the top of the trunk for it to evaporate through. To dry the trunk out, you can remove the trunk mat and leave it outside on a hot day, and also leave the trunk open all day in the heat, and it will dry the mat and trunk out for the short term. But when the car gets rained on again the problem comes right back.

The only way to cure the problem is to replace the gaskets, which isn't that difficult. You can order the gaskets online through several of the online vendors (usually dealerships) of Acura parts. Again, to emphasize, these are the gaskets that go between the taillight assemblies and the body of the car. They don't cost very much. If you would prefer to have it done, your trusted expert NSX mechanic (you do have one of these, don't you?) should be able to handle it with ease.

The secondary problem is that the top seam of the taillight lenses opens up with age. If you take a close look at the top of your taillight lenses, you will see that the top seam is opened up. This isn't hard to see at all, they open up along the top in plain view. (The center section usually doesn't open up.) Run a thin bead of silicone along this seam on both taillight lenses to seal up the top seam. This will prevent any moisture from coming through that seam.

If you do both of these things it will completely cure the wet trunk problem. I had the same problem, and after completing both tasks, the trunk is completely dry now.
 
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Thank you for all of your suggestions. Jett, I will follow both of your steps with my trusted mechanics doing the task. However, I have one last thing, as you said "center lense usually don't have this problem", my center lense is also moist, if not, the worst one. Is there other problems associated with mine situation or if it is pretty much the same?
 
I have not seen a center lense with moisture. The center lense has only a short run of lense, usually not enough length to allow it to open up at the seam. I suppose it is possible for the seam to open up, but I think it is more likely that any moisture in the center lense is entering from the rear. When the taillight gaskets are replaced and the trunk is dried out, there shouldn't be any moisture present in the trunk to enter from the rear. So replace the gaskets first then seal the lenses after the moisture evaporates. If you do these two steps I think it will completely take care of the problem.

Do the gaskets first, then wait to seal the top seams for a few weeks, to let residual moisture evaporate out of the lenses. If you seal them with moisture inside, the moisture will remain trapped there. So it is important to let them dry out as much as possible. You may be able to blow some hot air through them with a hair dryer by removing the bulb connectors from the back and pushing some air through there to dry them out. I have never tried this particular step but I have read that it is possible. I have also read about people drilling small (1/8") holes in the perimeter of the lenses in a hidden spot to facilitate "drainage", but in actuality I think it was more for aeration than drainage. A little air circulation would probably dry the lenses out completely and eliminate any small amount of residual moisture remaining. Only after you are satisfied that the lenses are as dry as you can get them should you then seal up the top seams with silicone sealer.
 
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I had all of the same problems that you have have and it was a combination of three problems causing this.
#1 The PO left a wet car cover in the trunk so the stink was irreversible and the carpet had to be replaced despite my MANY efforts to fumigate the odor out of it.
#2 The gaskets were old and in pretty bad shape (normal for that age).
#3 the lights were opened at the top and a few other spots letting water in them from rain and mostly car washes (since i don't drive my car in rain).

I am very particular about my NSX so i bought all new gaskets from Acura (more expensive than they should be) and bought new tail lights as well. Now no problems.

You can try to seal the tail lights with silicone but i'm not sure how well that will work or for how long not to mention that it will be visible and noticeable so you should probably just keep your eyes out for a nice set tail lights if your going to spring for new gaskets and or trunk carpet.

If your on a budget and just want a cheap fix then dry everything out REAL GOOD (i mean REAL GOOD!), buy some generic weather stripping material from Pep Boys or somewhere else and make your own new gaskets using your old ones as templates and then silicone up those tail lights good. Check the entire lights for openings as mine where also bowed at the bottom and they were pretty much not sealed anywhere very good. A better practice would be to bake them open in the oven (center lens letter removal trick) and then completely reseal them when you wipe them clean and put them back together.

You should be able to find all of the directions you need in great detail with the use of the search function here on Prime. Good luck.
 
This is a common problem. I have experienced the condensation problem in my taillights but my solution is different than most here. The taillight gasket that everyone speaks of seals the light housing against the trunk, it does not have anything to do with condensation in the lens itself. The lens is a sealed unit. As mentioned above, you can drill a small hole in the bottom of the outside of the lens, but this doesn't always work. Removing the bulb housing and drying each lens does work however.

The moisture in the trunk causing the corrosion and smell may be due to the taillight gaskets or, it could be coming from other areas as well. Perhaps the antenna mast or the trunk lid seal. You may have to do some investigating to find the exact culprit. Your trunk carpet must be thoroughly shampooed and dried, and still you may not be able to remove the musty smell.

HTH
 
Okay everyone, I went ahead and removed the carpet myself. I remove all of the tags and screws that holds the carpet onto the trunk, and proceeded to remove the carpet. However, I found that the part that is close to the engine side is attached to the trunk weather proof gasket (please excuse me if I called it wrong. It is the big rubber thingy that goes around the trunk) via a "see-thru"plastic stripe (sort of like a long ruler with both end that has some sort of rail or clip that the rubber attached to the top and the carpet attached to the bottom). I didn't want to force it out so I went ahead and remove the whole rubbert gasket along with the carpet. I hope I didn't ruin anything because I wasn't sure if the gasket was glued to the trunk or not (it came off rather easily but I can see on some area with it attached to the trunk, it looks like it has either glue mark or just dusts settled in).

After I remove the carpet, I can see the sponge on the bottom of the carpet is still damp. In addition, I also removed the tool kit box and the bottom of the tool kit box which had sponge is also fairly damp. I am going dry the sponge out in the next few days, spray some air freshner and see how it goes before I put them back in.

I think I can put them back in the same way I took them out, however, I want to make sure I don't need anything else, as I tried to look everywhere for some instruction on how to put them back but I can't seem to find anything. The point is that I wasn't sure if I need things like glues (maybe) to glue down the rubbers? Thanks for all of your help.
 
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The trunk-lid rubber moulding is supposed to be connected to the carpet. It sounds like you did the right thing. As for the carpet and air freshener, you are going to have to make a bigger effort than that to eliminate the odor that you spoke of. The odor is likely mold spores. Those spores will live through the drying process and continue to spread after you reinstall the carpet (ask me how I know). Do it right while you have the carpet out, have it professionally cleaned, or at the least go rent a carpet cleaner and use a disinfectant.

Good luck.
 
I just purchased a set (4) of the gaskets. If you want here are the part numbers and what I paid for them:
33503-SLO-A01 $14.79
33505-SLO-A01 $24.73
33553-SLO-A01 $14.79
33555-SLO-A01 $24.73

Brad
 
Okay, the carpet was okay, no mold. The cushion/padding underneath was damp, but again, no mold. I even digged up the tool tray and the padding underneath was damp and no mold. I dried up everything by blow dryer and good old California sunshine. Sprayed some fabrez and everything is good to go. I was able to put everything back the way it was (and maybe even better... pat myself on the back.. :biggrin::biggrin::biggrin:) and even my CD Changer performs better now(Probably psychological....). Now, for step 2, I guess I will employ the help of my trusted Acura Mechanic....

Just to be clear, do I just go and purchase the 4 gaskets as described below (thanks OLDMNSX... Can you tell me where you ordered them?):

33503-SLO-A01 $14.79
33505-SLO-A01 $24.73
33553-SLO-A01 $14.79
33555-SLO-A01 $24.73

wait for the lenses to completely dried out (Can I just let it dry under the sun or should I do something else to speed along), replace the gaskets and apply sealant to any opennings on the top of the lights, and I am good to go?

Thanks everyone for helping.... I couldn't do it without all of you... :biggrin:
 
I buy all of my Acura parts from Tim at Ray Laks Acura 1-888-ray-laks. Tim is a great guy, has the best prices i've found and offers free shipping. I bought my tl gaskets from him and yes, you should replace all 4 of them. I can't offer any help on the silicone as i replaced my tail lights when i went through this.
 
...wait for the lenses to completely dried out (Can I just let it dry under the sun or should I do something else to speed along), replace the gaskets and apply sealant to any opennings on the top of the lights, and I am good to go?

You can unplug the bulbs and blow some warm air through there with a blow-dryer, but letting them completely dry out in the sun is probably best. Or both an hour with a dryer and a week in the sun might be okay. Don't let the car get wet while waiting, or you will have moisture in them again! Once you are satisfied that they are as dry as you can get them, seal them with silicone sealer. Then you should be good to go.
 
Okay everyone, I am seeing that the gasket you are talking about is to be installed to the back of the light lamps. I got that and will order tham. However, upon inspection, when I open the trunk and look at the top of the lights, where there are hard plastic like cover (black) along the end of the trunk and on top of the lenses, there are in multiple sections and have small open spaces in between the sections. There are rubber/gasket like material underneath and you can put your finger in the small open spaces in between the sections and touch the rubbers. I see there is one particular open spaces where the rubber is sort of broke and doesn't fill the whole open space. Is this one of the culprit of the leak? Do I need to purchase other parts to fix the problem?

One reason I am asking this is that both of my taillights lamps are now dry out. However, the center one is still very much condesated, and I don't see any improvement. I am not sure if the abovementioned problem contributed to this. Please advise. Thanks for all of your help.
 
I just went through this entire process this fall. I had a terrible trunk leak that was completely solved by replacing the tailight gaskets. But, the gaskets just stop the water from getting in your trunk. They do not stop taillight condensation.

The rubber-like material you describe is the culprit. It forms a seal between the colored lens and the black housing and is where the water is getting in. Mine was cracked and brittle when I inspected it. There were gaps too, which are caused by the plastic warping over the years. To repair, I scraped as much of the brittle crud off of the seam and cleaned with alcohol. I then ran a bead of 100% clear silicone sealant around the entire seam where the red lens meets the black housing, making sure to fill any obvious gaps. Here's the kicker, even this did not stop the condensation. :o I think I might know why.

After my silicone seal job, the lights stayed dry after rain or a car wash. But, I noticed I condensation after rapid temperature or humidity changes in the air. Even with the bulbs screwed in, air can still get into the taillights through metal vents on the interior side. That means moisture-laden air can still get inside the lights, and, when there is a temperature or dew point change, that moisture will condense in the lens.

I think the only permanent solution to the problem is not in sealing the lenses, but better ventilating them so that the humid air can be removed more quickly. Sort of like putting a vent fan in your bathroom. So, I think that the solution of drilling small holes in the bottom of the lens is probably your best bet. I am loathe to scar up my lights, but I might try this too later in the spring.

Okay everyone, I am seeing that the gasket you are talking about is to be installed to the back of the light lamps. I got that and will order tham. However, upon inspection, when I open the trunk and look at the top of the lights, where there are hard plastic like cover (black) along the end of the trunk and on top of the lenses, there are in multiple sections and have small open spaces in between the sections. There are rubber/gasket like material underneath and you can put your finger in the small open spaces in between the sections and touch the rubbers. I see there is one particular open spaces where the rubber is sort of broke and doesn't fill the whole open space. Is this one of the culprit of the leak? Do I need to purchase other parts to fix the problem?

One reason I am asking this is that both of my taillights lamps are now dry out. However, the center one is still very much condesated, and I don't see any improvement. I am not sure if the abovementioned problem contributed to this. Please advise. Thanks for all of your help.
 
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Hi guys, here is a picture on the part that I was referring to:

fn4507.jpg


3536wjk.jpg


Is there a specific part that I can buy to replace the broken rubber?

Thanks for your help.
 
I think Honch has the right idea about installing a fan in the lens. I have a 2004 and I have condensation and there is no seam split in the lights. Something small like a computer fan should do the trick and it can operate only when the car is in use. I wouldn't drill holes in the bottom as this will continue to allow the humid air in, not to mention rain and car wash spray. If a fan can be installed the increase in pressure will allow the air to escape through where it came in, through the bulb holes or a vent hole can be installed into the trunk to assist in the airflow if the bulbs are too restrictive.

I haven't had a chance to see how this could be done, perhaps someone with more experience can check it out and let us know.

Tytus
 
The problem with a fan in the lenses, aside from where you would put it, is that there is some sort of plastic divider between the back of the housing and the front of the lens. This inhibits air circulation within the lens even more. It's why we have to sit there with a hair dryer for 20 minutes to dry out these little taillights! :) The problem really has to do with a pathway for air circulation, rather than forcing air into the light assembly. Think about your house. If you open a window, there is not a lot of air coming out. But, if you then open your door, you get a nice breeze through the window. Same idea here. Right now, we have an open window in the rear vents, but a closed door on the lens side, i.e., no place for the air to go. Ventillating the lens side of the unit gives the moist air a place to exit, plus the added benefit of moving the air on the side of the plastic divider thingy that really needs to be evacuated. Even if water got in through the holes, the positive ventillation means that it won't stay in there, which is the real problem with condensation.


I think Honch has the right idea about installing a fan in the lens. I have a 2004 and I have condensation and there is no seam split in the lights. Something small like a computer fan should do the trick and it can operate only when the car is in use. I wouldn't drill holes in the bottom as this will continue to allow the humid air in, not to mention rain and car wash spray. If a fan can be installed the increase in pressure will allow the air to escape through where it came in, through the bulb holes or a vent hole can be installed into the trunk to assist in the airflow if the bulbs are too restrictive.

I haven't had a chance to see how this could be done, perhaps someone with more experience can check it out and let us know.

Tytus
 
How do you open the center lamp up? I would like to get it open and remove all of the moisture. Looks like it doesn't want to go away...

:mad:

Most people bake it open in the oven. It has been discussed many times here on prime before. Most people bake it open to remove the "acura" letters. You might want to do that while you have it open.:wink:
 
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