Rear lights condensating on MG4 SE

[tsedge]

Sealed light units are not airtight therefore there is no need for any holes which would increase condensation as more water vapour would be contained within the unit. The fog lights on my z4 are full of condensation because the gaskets have hardened and are no longer sealing.
Your example of the drinks bottle is stretching it….literally . The bottle, made from pet, is extremely thin walled at 0.25mm and will flex easily when subjected to an increase or decrease in pressure/volume. A rear light, made from 3mm PMMA, is a well known dimensionally stable polymer, it wouldn’t deform with the slight increase/decrease in pressure caused by the Sun/cold even if it was fully airtight, which it isn’t. Don’t drill holes into light units, it’s an internet lie, it will only allow more moisture heavy air into the light and more condensation, this is the problem with the mg4 light, the seals are not doing their job correctly. It could be a poor choice of material, a design or assembly error?

My money is on a design error, probably didn't test for this. But, as said, it is common on many vehicles.

 

[dickturpin]

Has anybody else noticed this on the 4 another to add to the list for my dealer
Les



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Snap Les mine is same as yours also do you have problem with “lane keep assist mine is was always trying to pull wheel out of my hands, I just turn it off before every journey not happy with this. Tony

 

[KDP]

Yes mine does the same, but always disappears after a while.

 

[avhation]

Has anybody else noticed this on the 4 another to add to the list for my dealer
Les



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Yes, Les, I noticed condensation a few days ago soon after purchase, but today the weather here is cold but dry and without sun, and the condensation has cleared. When washing thecar take care not to point the hose towards the small holes which should allow the spoiler to breathe.

 

[Les burrows]

Yes, Les, I noticed condensation a few days ago soon after purchase, but today the weather here is cold but dry and without sun, and the condensation has cleared. When washing thecar take care not to point the hose towards the small holes which should allow the spoiler to breathe.

Hi thank you for your post any chance you could post a picture of where these small holes whichyou write about are please I’m not sure I have seen any holes on my wife’s 4SE SR
Les

 

[avhation]

Hi thank you for your any chance you could post a picture of where these small holes which you write about are please I’m not sure I have seen any holes on my wife’s 4SE SR
Les

Perhaps I've got the wrong end of the stick? The 2 small holes I've spotted are in the 4 Trophy boot lid light cluster.

 

[nexia201]

They all do that. Clears in the warmth.....eventually.

but will damage the leds in the long run and is not nice to the eyes

 

[Les burrows]

Snap Les mine is same as yours also do you have problem with “lane keep assist mine is was always trying to pull wheel out of my hands, I just turn it off before every journey not happy with this. Tony

Tony, sorry for the very late reply to your question about LKA hadn’t noticed, yeh same problem there from picking up the car but thankfully it does stay switched off, well it did turn it’s self back on once about a week after turning it off the first time but maybe the misses had been trying to tune the radio anyhow turn off again and it’s stayed off since, did mentioned it to dealer and he’s said there could be a software up date come for, it I know some have complained they have to turn it off every time they use the car but not on my wife’s.
Les

 

[Les burrows]

but will damage the leds in the long run and is not nice to the eyes

I agree and these lights will not come cheap as they are a unit not just bulbs and the whole thing will need to be changed.
Les

 

[Nikkwarn55]

Yes, my Mg4 has had condensation in the rear lights within the first week I bought it.
This could well go mouldy in warmer weather bit of a shame.

 

[Les burrows]

Quick up date had my wife’s car in the dealership for the last 48 hrs or more trying to get several issues on the car addressed in regard to this one condensation in the rear lights was told this is normal the lights are breathable and this can happen so nothing can be done about it so looks like we have to live with it hopefully if it’s going to fail or rust it will do it while still in warranty. Not great is it.
Les

Snap Les mine is same as yours also do you have problem with “lane keep assist mine is was always trying to pull wheel out of my hands, I just turn it off before every journey not happy with this. Tony

Tony wife’s four has had its update to day re the doors not opening on LKA defaults to on now but its to earlier to stay but its not like it was before what I mean is it’s not as aggressive and now you get an audible warning on your drift from the lane but only seems to work at around 35mph which is what the handbook stay it should but you can still turn it off but you need to do it every time you start the vehicle I think not to sure only just got it back but when I asked about it they said yes it default to ON as that is require to satisfy NCAP ratings.
Les

Got to stop typing posts on my phone

 

[tsedge]

I am a bit baffled about the condensation-is-a-problem discussion.

Taillights and headlights are ventilated and so both can suffer from condensation. That's a normal effect and there's a ton of resources online explaining why and how it happens. Twas ever thus.

You cannot eliminate this unless you invested in pressurised headlights with a non fogging gas or something complex and failure prone like that.

It is worse with modern cars because we have LEDs that typically give off less heat than incandescent bulbs and our lights are much bigger so there's a larger volume of air inside for condensation to occur.

Now, perhaps the MG4s lights are particularly bad for condensation and don't ventilate very well - but it remains to be seen if this causes any long term problems.

The bulbs and LEDs in modern vehicles are designed to cope with condensation, so it is unlikely that units will fail due to that. Condensation is as old as the hills.

I understand it is unsightly and would be better if it didn't happen. Are there any manufacturers who have achieved that though?

 

[Torryhun]

I am a bit baffled about the condensation-is-a-problem discussion.

Taillights and headlights are ventilated and so both can suffer from condensation. That's a normal effect and there's a ton of resources online explaining why and how it happens. Twas ever thus.

You cannot eliminate this unless you invested in pressurised headlights with a non fogging gas or something complex and failure prone like that.

It is worse with modern cars because we have LEDs that typically give off less heat than incandescent bulbs and our lights are much bigger so there's a larger volume of air inside for condensation to occur.

Now, perhaps the MG4s lights are particularly bad for condensation and don't ventilate very well - but it remains to be seen if this causes any long term problems.

The bulbs and LEDs in modern vehicles are designed to cope with condensation, so it is unlikely that units will fail due to that. Condensation is as old as the hills.

I understand it is unsightly and would be better if it didn't happen. Are there any manufacturers who have achieved that though?

You are correct, this condition occurs in every cars lights especially in winter, and LED's with less heat appears to be worse, but as summer approaches it should stabilise

 

[Hallix73]

Quick up date had my wife’s car in the dealership for the last 48 hrs or more trying to get several issues on the car addressed in regard to this one condensation in the rear lights was told this is normal the lights are breathable and this can happen so nothing can be done about it so looks like we have to live with it hopefully if it’s going to fail or rust it will do it while still in warranty. Not great is it.
Les

I am sure the condensation is only in the clear plastic (cosmetic surround) of the tail lights. The actual LED light bars looked sealed. Agree not ideal and hopefully the clear pastic surround wont stain on the inside. Time will tell. If it did then dealer would have to remove the outer plastic cover and clean it.

 

[Yorkshire Hillbilly]

Mine's mostly around the rear badge area. It makes the car look cheap.

 

[AndyL61]

Mine's mostly around the rear badge area. It makes the car look cheap

It is cheap, that why most people went for it.

 

[Yorkshire Hillbilly]

Wouldn’t take much to either seal them properly or engineer them to vent the condensation properly. It’s corner cutting, like removing the attention camera from the top of the steering column instead of fixing the software.

 

[bowfer]

You are correct, this condition occurs in every cars lights especially in winter

Literally doesn’t.
Dozens of cars, the only ones that have displayed misting are the MG ( rear ) and Polos we’ve had ( headlights ).
Other cars, not a hint of it.

 

[tsedge]

Lots of cars have it - here's an example with Porsches:

How to stop rear tail light misting/condensation ? - Rennlist - Porsche Discussion Forums

991 GT3, GT3RS, GT2RS and 911R - How to stop rear tail light misting/condensation ? - Has anyone found a workaround for this its frankly very annoying ? Can you seal them up ?

rennlist.com

I would like a solution though. I think it is the massive size of it that creates a lot of the problems.

 

[tsedge]

Wouldn’t take much to either seal them properly or engineer them to vent the condensation properly. It’s corner cutting, like removing the attention camera from the top of the steering column instead of fixing the software.

You can't seal them without a pressurised gas, which is unworkable, they need to vent to allow condensation out.

It's the size of modern rear lights plus the lack of heat from the LEDs that cause the problem.