Water/Condensation in Lighting Assemblies

[super20g]

Particularly the tail lights (but also fog lights and headlights at times) fog up on my car in humid/wet conditions and usually dry out a few days later. Depending on the conditions the fog will turn into water droplets.

I had the worst tail lights replaced a few months ago but even the replacements still do this... The senior service advisor at my service center said that this is expected behavior since all of the lights are vented.

My questions are:

• Do other manufacturers use this vented design? Do they also have this problem?
• Should we just expect on rainy, humid, car wash days for our cars to have moisture inside the assemblies?
• Are the bulbs designed to get wet? Wouldn't the metal contacts corrode over time with repeated exposure to moisture?
• Anyone know if there is a NHSTA report on this issue?

I do not usually see other cars with water in their tail light assemblies driving around. Occasionally in a car with a bad assembly / and old beater car, but surely not on new model cars... Not even on my older vehicles does this occur.

The below pictures were taken in a mix of environments. Freezing weather, rainy days, car washes, etc.

 

[chronopc]

I would take your car to the SC. I don't think the lights are supposed to do that.

 

[Swampgator]

Taillights were a known issue. My were replaced by a mobile tech a couple of months after purchase. The fog lights can look like there is condensation because water hangs underneath them.
Not sure about headlights, but I would call for a service appointment for sure.

 

[super20g]

I would take your car to the SC. I don't think the lights are supposed to do that.

I generally work with my service adviser via email and then he will setup service for issues he thinks he can look into.

This time, for the lights fogging up again after prior replacement, I mainly mentioned that they have been fogging up again when it has been freezing out. His follow up was "This is normal when it gets extremely cold outside as per the engineering article. As long as there is not water pooling inside the assemblies and the condensation goes away eventually, this is normal."

Not sure what engineering article he is referring to. I did push back and ask if it would be helpful if some of us reported the concern to the NHTSA since presumably this could affect reliability of the lights if nothing else. I have not yet heard back.

Perhaps this is not a big issue since it eventually clears up and I am just annoyed and need to move on. I just haven't seen this behavior with any of my prior cars let alone a brand new one where the manufacture tells you this is normal as long as it eventually goes away and doesn't start pooling.

 

[Funkmobile]

I've been told by the techs at the Vancouver Service Centre that the taillights have vents (and thus not sealed) so the condensation inside of them is "normal". They have refused to replace them if they are just fogged up. You need to have a mini pond inside of them before they'll consider replacing them.

 

[chronopc]

I've been told by the techs at the Vancouver Service Centre that the taillights have vents (and thus not sealed) so the condensation inside of them is "normal". They have refused to replace them if they are just fogged up. You need to have a mini pond inside of them before they'll consider replacing them.

I've never experienced condensation with mine. I've driven through all sorts of weather conditions including snow.

 

[SummerRain]

I've been told by the techs at the Vancouver Service Centre that the taillights have vents (and thus not sealed) so the condensation inside of them is "normal". They have refused to replace them if they are just fogged up. You need to have a mini pond inside of them before they'll consider replacing them.

I have the same experience as you

 

[Big Earl]

I would take your car to the SC. I don't think the lights are supposed to do that.

The lights are not sealed. In some high humidity weather conditions, it's possible for moisture to condense inside of the fixtures. Since they're open to the atmosphere, this moisture should dry out quickly.

If the lights have water building up and puddling in them, a service visit is warranted.

 

[kengchang]

Saw condensation today on my friends Ford Explorer tail light, so not a Tesla exclusive

 

[super20g]

Saw condensation today on my friends Ford Explorer tail light, so not a Tesla exclusive

My question would be was it just a bad seal / assembly on that one vehicle or do all of the Ford Explorer tail lights exhibit the same behavior as the Tesla lights.

 

[chronopc]

The lights are not sealed. In some high humidity weather conditions, it's possible for moisture to condense inside of the fixtures. Since they're open to the atmosphere, this moisture should dry out quickly.

If the lights have water building up and puddling in them, a service visit is warranted.

I guess there's not much humidity where I am.

 

[BOBEDIGITL]

My tail lights were like that (probably worse) and they swapped them out no problem at the Buena Park service center. Never had any issues regarding water/condensation in either my headlights or fog lights

 

[eCharcoal]

To me this is just wrong. All the cars I’ve owned over the years did not have this problem. A light housing on a car should be sealed so moisture can’t get in and mess up the electrical. Why would it need venting? Older and cheaper cars that have incandescent light bulb did not need to vent. This is LED which generates less heat.
To me it sounds like they’re making this venting theory so they don’t need to replace any more lights.

 

[borka105]

Should be replaced. My right rear light was replaced and looked just like yours. Hasn’t happened since...

 

[SJC3]

Most other cars are vented as well, but much better as Ive never seen condensation in my other 30+ cars at the level you’re experiencing. Unacceptable imo.

 

[pipestem]

I met a service tech at a supercharger location and asked him about it. He said call the SC and they would fix it. I've been waiting to see if anything else happens before calling (so far not). I have what I would call a minor amount of condensation in just one of the 4 tail light assemblies. The fact that it is just one is enough to tell you this is not an expected design. I call BS on that expected venting story.

 

[irelandm]

I have noticed a bit of condensation in my driver's side tail light, and it definitely seems humidity/temperature dependent. I actually considered a service call for it, but the closest service centre is 400km away, so it's a non-trivial trip (especially if we stay for the weekend, which is often the case). It does bother me a little because it seems maybe more like a flaw than a design choice.

However, it hasn't (yet) caused me any issues. I'm both glad and annoyed that I'm not the only one.

 

[AlanSubie4Life]

Agreed that this should not be an issue. The venting is normal and the choice on many modern vehicles (see attached - the blue circle is one of the breather vents for a Spark EV taillight - there are several, for several compartments). The purpose of the vent is to prevent this condensation issue, though. It is supposed to allow water to breath through the Gore-Tex membrane.

I think if you are seeing accumulation of moisture which is persistent, the membrane is either incorrectly installed or there is a crack or hole somewhere in the light assembly which is overwhelming the breather.

I could imagine that sudden transitions from a prolonged period in a high temp, very high dewpoint region to a region which is much colder (this would be pretty rare) could overwhelm the breather...but still seems like it should not be a problem in general.

A primer:

https://www.gore.com/sites/g/files/...er-Venting-solutions-for-clear-visibility.pdf