: very bad condensation in the headlight assembly:-/



STS-4000
07-26-12, 05:46 AM
hey guys, i just had a big rain storm here in KCMO and both of my headlights has moisture inside them. the passenger side headlight has about an half inch of water inside the assembly. is there a way i can save them before the water ruins them?

8323matt
07-26-12, 08:37 AM
This happened to me a while back. I tried removing the headlight assembly dumping the water out and using a blow drier to dry it out. It worked good with only a couple tiny water spot stains. Then I changed the bulbs and the foam seal must of not been on correct and got dust in it. So I removed it again and put it in the oven and removed the plastic lens and cleaned it out. Now its back to normal but it was a lot of work

STS-4000
07-26-12, 12:05 PM
What did you use to seal the plastic lens back up with?

8323matt
07-26-12, 01:12 PM
The factory seal and some clear silicone in some parts. If I remember correctly there is a write up about this

STS-4000
07-26-12, 01:43 PM
Ah okay. Well I have another question, do you know if that half inch of water within the headlight will evaporate over time? Or will I have to remove the headlight and pour it out?

eatyoursandwich
07-26-12, 03:03 PM
Ah okay. Well I have another question, do you know if that half inch of water within the headlight will evaporate over time? Or will I have to remove the headlight and pour it out?

I'm not sure if I would be willing to chance that. I'm not positive, but I doubt a half inch of water would evaporate -- even under high temperatures (100 degrees). Eventually, it's going to leave a residue that is a PITA to remove -- I would take the headlights off, drain the water, air dry any moisture and seal the hell out of them. I used industrial aquarium clear silicone after filling in the little cracks with clear resin.

8323matt
07-26-12, 03:20 PM
Like eatyoursandwich said, I wouldn't chance a couple hundred dollar headlight. I can almost guarantee it will leave water spots on the plasti-chrome if you leave it. Usually rain percipitaion is hard water.

STS-4000
07-26-12, 05:20 PM
Alright Thanks guys, I'm going to remove the headlights this Saturday and try to air dry them. do you guys think the bulbs and headlight assembly will be fine until then? I'm not going to drive the car for the rest of the week if that helps any.

8323matt
07-26-12, 11:04 PM
I think you will be alright. If you don't want to remove the headlight from the car you can suck the water out with a shop-vac if you have one. Might make life a little easier. If you are removing it from the vehicle, there is a bolt on the bottom of the headlight assy. that you need to drop the right side bumper cover to get to. Let me know if you need more help

By the way eBay has a lot of passenger side headlight ass. For sale but few drivers side

8323matt
07-26-12, 11:10 PM
I must of missed the word both in your first statement ha! For the drivers side just take the plastic cover of the back to air out. Then when all is good buy a new cheap foam seal (junk) or use some rtv silicone

STS-4000
07-27-12, 02:11 AM
Thanks Man, once I get the headlights out I'm gonna seal the crap out those things. and I'll be sure to let know if I need any more help. Thanks again.

BaTu
07-27-12, 10:55 AM
Search here under headlight "moisture" or "condensation" there are Tons of posts on this...

Basically, the water enters from a bad seal between the body and clear lens. You should pull them Both and reseal that joint.

If you leave water in there it will corrode the inside and you'll need to replace the entire, expensive, headlight. It will NOT evaporate as fast as it accumulates unless you live in the desert ;)

scott9001
07-27-12, 10:30 PM
i threw a gel (silaca) package in the back of my light threw the side compartment and dried up all the moisture if you can get all water out thats all id do first then your not out anything!

STS-4000
07-27-12, 11:07 PM
Where can I get those gel packages?

DarkMingBlueSTS
07-27-12, 11:57 PM
Basically you can get them from any boxed up item...I put some packs in my headlights yesterday so now I'm just waiting for some rain(it shouldn't take long as I live in FL) :)

BaTu
07-28-12, 10:54 AM
This is a TERRIBLE idea.....

Those packets don't remove the moisture, they just concentrate it! That is, their hygroscopic properties draws the wetness to them, they they hold that "wetness" until they can't adsorb any more. You have a gooey packet living in there.

Just do it right, quit looking for the Quick Fix ;) (besides don't you have to remove the bumpercover & grill to be able to throw the packet in? Heck you're 1/2 way to doing it right at that point)

DarkMingBlueSTS
07-28-12, 01:00 PM
Is the $400 replacement the only correct fix? Ba

BaTu
07-28-12, 02:03 PM
No, I fixed mine 2yrs ago, haven't seen a drop since...

Read post #12

DarkMingBlueSTS
07-28-12, 03:16 PM
Ok I read em ba...lol maybe i messed up there ;) how about this one...do you know of a way to remove the whole clear lens of the headlight assembly and fog/parking assembly?

BaTu
07-28-12, 04:05 PM
I believe it's possible to bake the entire assembly in your oven and soften the bond enough to separate the two pieces, I've never done though. My feeling is, although I'm sure it would be a better job, you'd be taking the risk of damaging it when you don't really have to...

curtc
07-28-12, 06:46 PM
This is what I'm dealing with right now, hoping it goes away, seems to be getting better.

BaTu
07-28-12, 07:11 PM
It's not going to "go away" on it's own, it's gonna get worse and ruin the housing :(

You need to reseal the housing or be prepared to buy a new one.

DarkMingBlueSTS
07-28-12, 11:04 PM
I would only want to take them apart to do some cleaning in there

DarkMingBlueSTS
07-28-12, 11:05 PM
If you're not already run your headlights as much as possible curt

curtc
07-28-12, 11:07 PM
If you're not already run your headlights as much as possible curt

Yep, been doing that. Doesn't help that its been humid almost everyday

8323matt
07-29-12, 02:05 PM
I wouldn't try removing the lens if this is your first time trying it on this expensive of a light. Trust me its hard, especially assembling it again.

Have you tried drying them out with a heat gun or blow drier yet?

8323matt
07-29-12, 02:10 PM
I would keep in mind you might get a hot spot on your bulb(s) with all of that condensation and a bulb(s) might bun out

buzz
08-03-12, 10:58 PM
This seems to be a significant problem with Cadillac STS from a variety of years. I occasionally have some condensation in the passenger side on my 2008; however, it dries up quickly and so far, has not caused any serious problems. Has anyone ever checked if there is a TSB from GM on this? If so, maybe there is a solution from the "experts"; not to say there aren't any experts contributing to this forum! I appreciate all the constructive assistance this forum offers, and I frequently take the suggestions seriously.

eatyoursandwich
08-05-12, 12:20 PM
This seems to be a significant problem with Cadillac STS from a variety of years. I occasionally have some condensation in the passenger side on my 2008; however, it dries up quickly and so far, has not caused any serious problems. Has anyone ever checked if there is a TSB from GM on this? If so, maybe there is a solution from the "experts"; not to say there aren't any experts contributing to this forum! I appreciate all the constructive assistance this forum offers, and I frequently take the suggestions seriously.

OK, let me try to clear things up here.

Is there a TSB? No. Will there ever be? Not likely. A TSB is only issued if it creates a safety hazard due to a defective design/part.

If you're under warranty and there is water that has built-up in the assembly, your dealer will replace it -- maybe with a little push back.

First off: The headlamps (both factory HID and halogen) are what is called passive systems -- which means air is allowed to enter and exit the assembly through a vent at the bottom of the assembly. This is mainly so the headlamps won't explode when you are driving at high altitudes -- Colorado, etc.

This means you can seal the living hell out of the outside of the housing and still get condensation. There are more factors involved than just how the lens is sealed to the housing -- bad gaskets on the access doors, clogged vents, poor seal on the headlamp electrical harness <-- if your housings are properly sealed, this is how most of the condensation is getting into the housings, but the vents are 'supposed' to allow a way up and out of the housing for the condensation.

That being said, there are numerous ways to fix the condensation -- the best way is obviously objective.

What I did after a few pressure tests with an engineering friend of mine: First, I used glass resin the fill the little cracks where the lens meets the housing -- probably not necessary, but I did it anyway. Then I applied a bead of industrial weather resistant silicone to the outside of the housing. Then, I replaced the gaskets on each access doors and applied silicone to the outside of each of those as well (I spent the extra money for lifetime D1S bulbs so I doubt I'll need to mess with the access doors for a while and if I do, I'll just pull out the heat gun). I completely sealed up the system -- housing, harness, vents, everything. Probably not the best idea if you live at high altitudes, but if I ever find myself driving to Colorado, I wont be taking the Caddy. I drilled a hole in 1 of the access doors on each side and use a rubber plug that I can take out and release the condensation if needed.

After a few high pressure washes and a good week of rain, not even an once of condensation -- going on about 6 months now.

If you really want/need to remove the lens from the housing, about the only way to do so is to leave each housing in the oven overnight at 140F.

Tried the silica packets, but I didn't feel like having to replace them and didn't feel like that was a permanent solution.

Am I recommending this method? Hell no. It's simply what I did and it seems to be working fine.

STS-4000
08-06-12, 06:12 PM
Okays guys here's an update.

I removed both headlight assemblies and let them air dry for a day, then I took some aquarium sealant and went around where the lens meets the body of the headlight assembly.

i then removed the side door panels from the headlights and put a small amount of aquarium sealant around the area where the foam gasket seats, after that I properly seated the foam gasket on top of the sealant.

While letting the sealant dry, I installed 6000k hid's in the fog lights (and man they look great!)

After letting the sealant dry I put the headlight assemblies and bumper back on and went to the car wash to test and see if the headlights will get any moisture build up behind the lenses.

I am pleased to say the headlight assemblies stayed dry as a desert :-D

BaTu
08-06-12, 08:16 PM
What is "Aquarium Sealant"? Think it's UV stable? You went to all that work and then decided to use Aquarium Sealant???

I donno, I hope it'll last, I used what was called "Windshield Sealant" (a thinned silicone) I assumed it was meant for outdoors & UV, not so sure about something for your aquarium ;)

Next, I didn't do anything to my foam gaskets. I don't believe they're the problem though. How much water could be getting to the Back of the housing? It's all behind the inner well and pan, I just don't see an issue with it getting drenched back there. I pressurized my housing (there are actually a few vents) and could see where the seal failed. It was Clearly, in My case, between the clear lens and the body...

eatyoursandwich
08-07-12, 10:51 AM
What is "Aquarium Sealant"? Think it's UV stable? You went to all that work and then decided to use Aquarium Sealant???

I donno, I hope it'll last, I used what was called "Windshield Sealant" (a thinned silicone) I assumed it was meant for outdoors & UV, not so sure about something for your aquarium ;)

Next, I didn't do anything to my foam gaskets. I don't believe they're the problem though. How much water could be getting to the Back of the housing? It's all behind the inner well and pan, I just don't see an issue with it getting drenched back there. I pressurized my housing (there are actually a few vents) and could see where the seal failed. It was Clearly, in My case, between the clear lens and the body...

To be honest, I just got sick of it and sealed every possible opening in the housing. I had already sealed the outside and was still getting condensation so I just replaced or resealed any components that could potentially let moisture in the housing.

As far as the aquarium sealant, well, it's actually just a super-strong silicone that they happen to use in industrial aquariums like you see at Seaworld, etc. but it's also used for many other applications. The product I found had, by far, the best combination or adhesion, life cycle, heat/UV resistance, and most importantly, it's clear. If this doesn't permanently seal the outside of the lenses, nothing will.

GE RTV-108


I'll be the first to admit, I'm sure I did some things were probably completely unnecessary, I just wanted this problem to go away, for good.

EChas3
08-10-12, 10:32 PM
I have read here (long ago) of a TSB or similar service notice informing dealers that some condensation is normal but 'excessive condensation' may require replacement under warranty.