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Burned Out Tail Light Segment

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mknox

Well-Known Member
Aug 7, 2012
10,104
1,901
Toronto, ON
Wondering if anyone else has seen this. I have had perpetual moisture in my tail light for some time now. In the summer, it will evaporate out after a few days, but since the weather has turned colder, it persists. It seems to get in when it rains or when the car is washed, yet I can find no signs of a crack or damage.

Today I noticed that part of the light is malfunctioning. It is the bottom part of the "circle" on the section that is affixed to the trunk lip. It is out but sometimes will flicker on and off. My guess is the water has fouled something up, and I assume the bulbs are LED but have no idea if they're user serviceable, or serviceable at all. I have an appointment on February 1st and will have it seen to then.

Here's a picture:

IMG_0046.jpg
 
My guess is that the moisture has finally corroded the printed circuit boards the LED modules are on and a break in the circuit occurred. Easiest is a replacement of that whole light module, although nothing is really wrong with it other than a bad connection somewhere. If you can ask for the part after they replace it, you could cut it open, find the break and resolder it and glue the whole thing back together and use it as a spare (if you're so inclined and handy...)

I've seen a few Model S's with a similar issue in the upper brake light. The LED boards are pretty durable, but moisture can cause corrosion which can interrupt the circuit, and long continuous boards are subject to thermal and vibrational forces that can cause circuit breaks over time.
 
The leds are not serviceable, it will require a tail light assembly replacement. Normally moisture will rust the power tracks of the circuit board untill they break or one led in the series will blow and take out the adjoining 3/4 in the series.
 
Wondering if anyone else has seen this. I have had perpetual moisture in my tail light for some time now. In the summer, it will evaporate out after a few days, but since the weather has turned colder, it persists.
You are one of the most active TMC members and I'm sure you are aware that the issue you describe is a common one, and well known to Tesla. Did you ever request that your Service Center replace the taillight seals? I did last year and they were happy to do so.
 
You are one of the most active TMC members and I'm sure you are aware that the issue you describe is a common one, and well known to Tesla. Did you ever request that your Service Center replace the taillight seals? I did last year and they were happy to do so.

The issue that I have seen which is common pertains to the white backup light. In that case, it is a second clear plastic lens that is part of the chrome strip getting moisture trapped between it and the white lens on the tail light assembly. That is really only a cosmetic problem because water is never actually getting inside the tail light assembly. Newer cars are coming with a revised chrome strip that no longer has the second plastic lens in it... just a hole.

My car has been in three times for that problem, and I still get moisture buildup in the backup lights that comes and goes. Each time they tell me that they have applied a "new and improved" sealing technique.

But that is not what I'm talking about here. In this case, moisture is getting in to the entire red lamp housing as you can see in my picture. Can you point me to any discussions where this has happened (i.e. water in the red tail light, not the white backup light)? I did a quick search before posting and didn't see anything.

The earliest Tesla can get me in is February 1st (primarily for another replacement DU that has been buzzing loudly since September 2014.
 
You are one of the most active TMC members and I'm sure you are aware that the issue you describe is a common one, and well known to Tesla. Did you ever request that your Service Center replace the taillight seals? I did last year and they were happy to do so.

I brought my new car in with the same issue and they told me there's nothing wrong and working as designed. They said the moisture is just at the seals and not in the light itself. Go figure.
 
I brought my new car in with the same issue and they told me there's nothing wrong and working as designed. They said the moisture is just at the seals and not in the light itself. Go figure.

Was yours in the white backup light or in the entire tail light as in my case above? I've had repeated issues with the backup light, but that is a different problem (see my explanation above). If just the backup light lens, it really is just a cosmetic issue. After the third attempt to seal the chrome strip with the lens for the backup light, my Service Center has basically said the same thing. I had hoped they would retrofit older cars with the new chrome strip that just has holes instead of the extra lens, but apparently they can't do that.
 
Was yours in the white backup light or in the entire tail light as in my case above? I've had repeated issues with the backup light, but that is a different problem (see my explanation above). If just the backup light lens, it really is just a cosmetic issue. After the third attempt to seal the chrome strip with the lens for the backup light, my Service Center has basically said the same thing. I had hoped they would retrofit older cars with the new chrome strip that just has holes instead of the extra lens, but apparently they can't do that.

Pardon my finger over the lens but that whiteish stuff in the seal is water after washing the car. It's on both sides.
ImageUploadedByTapatalk1452459041.342975.jpg
 
Pardon my finger over the lens but that whiteish stuff in the seal is water after washing the car. It's on both sides.

Thanks... and very interesting. I'd suggest making a fuss with Tesla over this since in my case, it seems to have caused damage to the LED lights in there.

EDIT: Wait, are you talking about the water right around the edges of the light? I get that all the time too on both sides. I sometimes blow it out after washing the car.
 
Thanks... and very interesting. I'd suggest making a fuss with Tesla over this since in my case, it seems to have caused damage to the LED lights in there.

EDIT: Wait, are you talking about the water right around the edges of the light? I get that all the time too on both sides. I sometimes blow it out after washing the car.

Yes the water around the edges. Sounds like you agree with the SvC which is good. [emoji3]
 
It starts in the seal from the reverse lights and migrates. The good news is that there is FINALLY a fix and I mean a true actual fix!! Bad news is that the entire assembly will have to be fixed but ask them for the updated reverse lift assembly it will fix this issue as well.
 
In what I quoted, mknox explicitkly said the "new chrome strip" that isn't being retrofitted into older cars. I was simply saying that the new version was installed on my 2013 car.

I find that interesting because when I enquired a while back, I thought they said that to do this, both tail light assemblies would have to be changed too. Something about how the strip integrates with the tail light. I have had the white backup light moisture problem forever (separate from the issue I raised in this thread) and was asking in that context.

I will definitely bring this up when my car goes in to be fixed.

- - - Updated - - -

It starts in the seal from the reverse lights and migrates. The good news is that there is FINALLY a fix and I mean a true actual fix!! Bad news is that the entire assembly will have to be fixed but ask them for the updated reverse lift assembly it will fix this issue as well.

I was told that the backup light moisture was only on the clear window that is part of the chrome strip, and that water wasn't getting into the tail light itself because there is another clear window on the tail light too. (i.e. moisture was getting trapped between the tail light lens and the chrome strip lens). Another thing to question when the car goes in.
 
I couldn't tell you if they had to change the lights or not (though I doubt it). I didn't even mention the moisture there. They were working on something else and called me to tell me they saw the moisture and ask if they could have the car a bit longer to replace the strip (I was supposed to come back within an hour or two to get my car).

That said, do the Canadian cars use the US tailights (all red) or the Euro taillights (amber turn lights)? If the latter, perhaps that plays a role.
 
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