[MartsCT200]

Ever since I bought this car, 2 years ago, my left rear light always had moist or condensation in it. This was always the case after a couple of days of rain or when it was cold damp weather.
Since it got worse, I finally took the light of to see if there was a leak or crack in it.

Luckily no cracks, but when turning the taillight upside down I saw water dripping out of the cornerseal.

This is how it looked

To get the condensation and waterdrops out I used a blowdryer in the lightbulb hole. Took me about 40 minutes until it was fully dry. I then used silicone and sealed all the edges and especially the spot were the water leaked out.
I let it dry overnight inside the house and then refitted the taillight.

So it's been raining for a few days now and although it is better than before, there's still some condensation in the light.
The right taillight has almost the same condensation on the same spot, so i guess it's normal for a 11 year old car and I can live with it

Removing the light is pretty straightforward and easy to find in this forum or on youtube.
Cheers!

 

[TobiasSing]

It's possible that the condensation is still left over from before, and that the sealant isn't entirely set and cured. I've had lights do this, but then later I realize they aren't leaking anymore. So I would hope this in your case, that it will soon stop having the condensation

 

[MartsCT200]

Yes I'm pretty sure it's not leaking anymore and I will just leave it as it is for now. I did notice that it's not uncommon even on newer cars. Saw a couple of cars in the parkinglot like Audi's, BMW and Tesla which also had the condensation in the taillights, and those were not older than 2019. So as long as my lights doesn't turn into tiny fishtanks I'm good

 

[MartsCT200]

Update: after a couple of weeks with rain and snowy weather the drops of water in the taillight are back....
I am sure I fully sealed the edges but apparently the water is getting in from somewhere else.

It's not as much waterdrops as before, but still. I will leave it for now and look into it when it's warmer weather.