Water Ingress in Rear Light Repairable?

[AntFR]

Hi all. Not long had a MK3 Leon and I have noticed there is condensation in the rear light cluster (outer cluster pictured). The light still works fine but my worry is that over time the moisture would corrode the electrics. I have seen videos of people easily removing the unit but not one showing someone repairing the existing light. It has been mentioned as a common issue but I would rather repair it than replace. Note it is the LED version so a replacement would cost considerably more than the standard bulb version but it would also harder to test I'm guessing (traditionally submerging in water with bulbs and electrics removed). Has anyone attempted to fix these? I know some people suggest drilling a hole inside to permit airflow but I would prefer it fully sealed so I would gently heat the light to hopefully evaporate the water and then fully seal the edges. If it is possible to fix are there any suggestions for identifying the crack and a good sealant to use?

Thanks

 

[Deleted member 139706]

I highly suggest just drilling a drain/vent hole and leaving it be.

I tried to do exactly what you want to do, repair it, reseal it, I tried everything. Silicone, plastic welding, glue, you name it I tried it, but unfortunately the cracking is in such a place and is so small and long, it's basically impossible to 'fix'. The good thing is, the way it cracks means that water can't ever really go anywhere near the LEDs/electrics, so it's not really a huge problem. I think the condensation would do more damage than running rain water.

I gave up after a while, drilled one or two wee tiny drain holes at the bottom, and I haven't had a drop of condensation since.

(FYI, this is a known problem that was originally solved by SEAT dealers replacing them. The crack is huge - fault is that the plastic around the studs for mounting the lights crack due to being overtorqued during manufacturing, causing the entire thing to hairline crack. If you pop yours out and look at the very top left, thinnest part, remove the mounting stud you'll see it!)

 

[R53Winny]

Yes.... Search as I previously did a post about it

 

[leonlad]

I bought a new light on aliexpress it does not come with the bulb holder but looks exactly the same as OE and only £43

 

[LeylandVCDS]

I tried drying out and resealing the cluster on my previous Leon, with no sucess at all. I just replaced it like for like from Euro Car Parts, never any issue with it from then on

 

[Mr Pig]

I think water ingress might be able to do damage. Part of the tail-light on my wife's car packed in and when I removed the light I could see water had been getting in. I can't link the two for sure but.

The other thing to check is the seal to the body. If this isn't good it can let water in too.

I didn't mess about with it. Just bought a used replacement off eBay and it's been fine so far.

 

[LeylandVCDS]

Failure of the seal between the light cluster and the body will allow water into the boot area, but there won't be any moisture ingress into the light cluster itself unless the seal on the cluster is at fault. Once that's gone and the inside of the light is wet, a new cluster is the only solution that's going to work.
I tried twice to reseal one of the outer clusters on my previous 64 plate, but it proved an impossible task