My stock headlight assembly leaked and filled one third of the way with water. I have stock H/L assembly and stock 'replacement Sylvania Silver Star 9005 high and 9006 low bulbs and side marker no. 194 bulbs. I have recently signed up with a automated car wash system that could be a factor. It is one of those $20.00 a month for one a day car wash. I have the new 9006 low and the no. 194 side marker bulb that blew with the excessive water. Any one having an idea where the water came in and how to keep it from happening again. Thanks, Jim

 

I have the passenger side back together and tested the 3 light bulbs before putting the tabs on the back of the H/L assembly. All three tested good. But if it is still leaking, I will be doing this again. Any reports on where where your Gen. 2 leaked ? Any ideas on sealing the lamp gasket on the base so they won't leak ? Thanks, Jim in SC

 

New bulbs come with new seals (at least the high and low beam bulbs do, the marker light has the seal on the socket itself). You should be able to buy new bulb sockets for the small marker light in most parts stores and just rob the seals from them for your existing sockets on the truck, if you suspect that to be the leak.

It's uncommon with stock unmolested lights, but it's possible that the seal between the back half and the lens is letting water get in. I say "unmolested" because the only time I've ever had water get in through that seal is after removing the lens from the light (opening it up, for a modification of some sort) and then trying to reseal it when reassembling. If you suspect this seal to be the cause, you could disassemble the light (pull the chrome trim ring off, it's just snapped into place, and pull the 4 metal clips around the light off), clean the area where the lens meets the back half very good all the way around, and apply a bead of clear silicone all the way around, being sure to work it into the crevasse between the two parts. Then reassemble.

The only other possibility is a crack in the housing somewhere that isn't immediately obvious. Check around all the mounting points, as that's typically where the cracks will form, because those areas see the most stress just from vibrations from driving acting on the mounting bracket holding the light in. Again, not super common, but a possibility none the less.

Worse case scenario, you can always replace the entire assemblies with some new aftermarket ones.

 

I didn't know you could open and reseal the composite H/L assembly. I wish I had access to a smoke tester. That would be one way to 'see' the leaking area. I was hoping to avoid buying a new assembly. They have come down , but are still a bit pricey. Right now I am trying to dry out both H/L assemblies and take a good look at them before I put them back on the Blazer. I do suspect the water forced on the front by the auto car wash is making the problem worse. Thanks for your helpful suggestions.

 

I didn't know you could open and reseal the composite H/L assembly. I wish I had access to a smoke tester. That would be one way to 'see' the leaking area. I was hoping to avoid buying a new assembly. They have come down , but are still a bit pricey. Right now I am trying to dry out both H/L assemblies and take a good look at them before I put them back on the Blazer. I do suspect the water forced on the front by the auto car wash is making the problem worse. Thanks for your helpful suggestions.

 

You could always try dunking them in water to test the lens seal. Clean up the bulb areas and put some tape over them (electrical tape, duct tape, anything you can make a good seal with temporarily). Fill the bath tub up, hold the lights lens facing up, and dunk them in and hold them under for a little while. Watch for water creeping in on the inside. If you get them dried out before hand, even better, because if they're dry when you start but there's water inside after the dunk, you have your answer.

They're not easy to separate, it's a process, but the lens does come off. What I was suggesting is to try and apply some silicone to the outside edge along where the two halves meet without removing the lens. Prying the two halves apart on older lights is more difficult than doing it to new ones I've found out. The only thing that I can assume is that heat cycles over the years makes the sealant more resistant to loosening up. I've broken my fair share of older used lights trying to open them up, however I've never had too much of an issue separating and opening up brand new lights.

 

Sorry for the double post. It was showing me I hadn't sent my post, so I sent it again. Now two posts appear ! Back to the problem at hand.....My beloved Blazer 2 door is an ex-cop car, which means it had a lot of lights and radio wiring that wasn't stock. To make it worse, to sell the old trooper, they rip out some of the wiring and leave some behind so you will wonder what was that for: an essential piece of wiring or remnants of the cop car era. In my driver's side composite head light assembly, there is a strange light plug between the stock side marker light and the low beam 9006 bulb. It is a strange blue light filament that is curved into a metal loop. It has three wire plug which makes me think it is a 'wig wag' blue light. It has a very poor seal against the housing which makes me think it is part of the leaking problem. No gasket or 'O' ring seal. I am trying to design a flat gasket I can cut out of some sheet of plastic or rubber. It is held on by two Phillips screws.

 

Yep, that would be a strobe light bulb. There's probably some in the tail lights too.

Working in an auto salvage yard, I see them a lot in vehicles that use to be law enforcement vehicles.

 

That's it, except mine is a dark blue. Mine even has the fine bare silver wire wrapped round the outside of the filament. I wondered if the wires could be a heat sink. In your photo above , it almost looks like tiny cracks in the 'glass' filament. That's probably it and explains why they strobe on only a fraction of a second. If they stayed on constantly, they would burn out. Yours even has a metal band that all the fine wires attach to. That band is probably attached to a heat sink in the base.

 

I got the passenger side assembly drained and the 9006 low and the no. 194 side marker bulbs replaced and all working. I then looked closely at the driver's side. It also had about three tablespoons of water in it. I took it apart and used silicone to seal the side marker light and the strobe light they had added into the wiring for Cop car use. Now after the tropical storm/ hurricane has flown by, it is all back together and ready to be tested. I am going to run it through the automated car wash today. Then we'll see if it is leaking. I always have trouble with the H/L assy tabs and fitting into the slots properly. I like the design and they are easy to remove, it is the RE fitting into the two slots you can't see are always a problem. I will get that done and go through the wash today. The weather is cooler today due to the Tropical storm.
If the passenger side leaks again, I will remove the assy and seal the side marker with silicone because it doesn't have a nice 'O' ring like the 9005/6 bulbs do.