Condensation in headlight

killer_crocs · Aug 14, 2024

I’ve been getting some (a lot of) condensation in both my headlights on my gen3.5. It’s not as bad on the driver side as it is on the passenger side. I don’t see any visible cracks on the housing.

Another thing to note is it started happening on the passenger side after my friend pulled out the high beam bulb on that side. I was trying to install the DRL resister kit and he mistakingly pulled out the high beam bulb and didn’t install it correctly.

A week later I went to go wash the car and notice the passenger side headlight fogging up. I checked and saw the high beam bulb was not installed correctly and fixed it. In the process I also pulled the high beam bulb from the drivers side to inspect and also the low beam bulbs form both side. The following day I noticed condensation on both headlights. Now every time it rains or I was the car both headlights fog up, however, it isn’t too bad on the drivers side.

I have tried everything to fix this including taking out all the bulbs on both side, using a hair dryer to get rid of the condensation, and install the bulbs with some dielectric grease around the o-rings. But as you can see it hasn’t helped.

Now my next suspicion is that maybe the rubber boot around the high or low beam bulbs is not seated correctly which may be causing this issue.

If anyone has any suggestions on what I can try it would be appreciated. Thanks.

Shiro_se · Aug 14, 2024

Is there not supposed to be some kind of cover on the back of the headlight housing? My Mazda6 was awful on burning up halogens and I was in there a lot (multiple times a year). Each section of those 4 lamp housings had access covers with gaskets to seal them. There was one on each end and one central one for the two lamps in the middle.

My BMW Z4 also has some condensation issues. It is from a weak foam seal on its housing covers. The only way to get a new seal is to buy the whole cover. I have put some sizable dessicant bags inside the housings and the problem has gone away. Not a true fix, but a solution.

MrCrudley · Oct 31, 2024

I have had this problem on my BL for a while now and have found a solution that worked for me. I think it also helps to attempt this on a dry but warm day where the headlight lens is full of water droplets. It was 28C when I did it.

I removed the high beam bulb and put the vacuum cleaner in the headlight bulb hole on the headlight assembly. Tuned the vacuum suction up to 11 and held it in place for about 20 minutes. It seemed to clean up faster when I used by finger to seal the vacuum nozzle and headlight assembly join.

This got it to about 80% clear. The stubborn droplets were coaxed out by the hairdryer set on maximum heat aimed at the problem areas. All done in 30 minutes. I suspect the upper side seal headlight seal has the leak so I've double taped it with Gorilla tape and will see how it goes before thinking about silicon. Finally happy since this has bothered me for ages.

Why Mazda can't make lights that don't suffer this problem is nothing more than a poor design executed brilliantly.

Condensation in headlight

Top Contributors this Month

Recommended Communities