Rear lights condensing on MG4 SE

[Tuareg]

My BMW 330D had condensation in the headlights, came and went, non-issue.

 

[CarbonEV]

My Trophy has really bad condensation tn the rear spoiler and both indicator units. After alot of hassle MG agreed to change them, two days latter it's back. On a sunny day it's really bad, look's a right mess. My dealer has not been of much use telling me to deal with MG directly.

This affected me day 1, at the time (November 2023) I just got told it was normal to expect it to happen and that it would “dry up” which they do for the most part after heating up.

Doesn’t happen on the front - only the rear.

I’ve just learned to live with it. Doesn’t look great at all but it is what it is I guess when it’s so widespread and replacing the clusters doesn’t seem to work.

 

[supe001]

The clear plastic on my car has cracked. Has anyone seen this before?
View attachment 18297View attachment 18298

I have the same small cracks all the way over the center light up by the window on my MG4 Luxury from April 2023. I discovered it because there is fog on the inside. I think the problem has been there from the start, as I have seen fog for a long time.

 

[David Hopwood]

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 wife's car has fogged on both rear lamps and the centre bar from day one.
As others have commented moisture should not be present in a LED cluster.
The car is going in next week for a new driver's side light as the moisture has corroded the electronics that drive the LEDs and half of the light is out. Not a 33 grand car?
Just to top things off it will only charge on rapid DC chargers, the AC home charger has stopped working. Maybe a coincidence but this seems to have happened after a recent software update

 

[tsedge]

Fogging of the rear lights is normal, common on many cars and has no fix.

 

[GlobalHealer69]

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?

And what do you think the inherent problem of whole vehicle vibrating at speeds over 70 mph which appears very common amongst owners ? As expected, my MG franchised Dealer's workshop pleaded totally ignorant of such problems and made the excuse that they couldn't replicate it as a road test over 70 mph would be illegal and therefore not possible.

 

[AndyL61]

My wife's car has fogged on both rear lamps and the center bar from day one
As others have commented moisture should not be present in a LED cluster
The car is going in next week for a new drivers side light as the moisture has corroded the electronics that drive the LEDS and half of the light is out.Not a 33 grand car?
Just to top things off it will only charge on rapid DC chargers , the AC home charger has stopped working. Maybe a coincidence but this seems to have happened after a recent software update

Your AC charging issue maybe a faulty CCU , which is a known common issue on the 64kWh battery cars.

 

[GlobalHealer69]

I suffered the same condensation problem in all the rear lamp clusters but, as I had only had the car a couple of days from new when I noticed it, I got the main MG dealer to replace them under 'Manufacturer's Warranty' as it was obviously their fault.

Now, I just have to get the inherent high speed vibration problem sorted by higher up as they state they can't replicate it above the legal speed limit. Nice try guys but I know my consumer rights, as they'll soon discover.

 

[GlobalHealer69]

Your AC charging issue maybe a faulty CCU , which is a known issue on the 64kwh battery cars.

So, if it's a 'Known issue' THEY are responsible, the Retailer in the first instance and then the Manufacturer.

 

[AndyL61]

So, if it's a 'Known issue' THEY are responsible, the Retailer in the first instance and then the Manufacturer.

Yes it would be covered under warranty if that is the case.

 

[GlobalHealer69]

Yes it would be covered under warranty if that is the case.

It was, but they kept me waiting 6 months until they swapped them out ! Can't blame Covid for that delay surely ?

 

[Tig170]

I get this from Nov - Feb each year (in the UK), I think its a characteristic of the car, by April its gone and all forgotten about (until Nov.), I think its condensation from humans rather than water ingress?

 

[PJWey]

Should not be happening I don’t think and it’s only on one side but yesterday while at a body shop sorting a repair out for my wife’s car I asked the chap there about it and he said it does happen on some cars the worse ones being Tesla.i will it address with the dealer next week
Les

MG Poole advised this is totally normal as the light cluster there is designed to work that way in cold weather.

 

[Jeroen]

Discussed this rear condensation issue with my dealer and MG’s official statement on this in the Netherlands is “product feature”. Doesn’t require repairs.

 

[OriginalBigAl]

I think that the light clusters are sealed units , if they were produced on humid days of which China has many then that humidity will be trapped inside and condense on cold days and stay as vapour on warmer days, apart from drilling small ventilation holes which could make it better or worse and lose a bit of value to the car, the only solution is to hassle the dealers or MG .

 

[CarbonEV]

I think that the light clusters are sealed units , if they were produced on humid days of which China has many then that humidity will be trapped inside and condense on cold days and stay as vapour on warmer days, apart from drilling small ventilation holes which could make it better or worse and lose a bit of value to the car, the only solution is to hassle the dealers or MG .

Surely if they swap them, you’ll still get the same issue anyway?

Mine did it from day 1 and after realising why, it’s not something you can “get rid of” if they’re designed like that.

 

[ozzz]

All lights do it except sealed units ,
Looks bad because u have a sealed unit with a cover on top not sealed so the gap between attracts moisture and condensation will be the result if it was double glazed no problem but then it is cost.
And yes sealed head lights are waterproof in Australia we used them for under water lights for swimming pools.

 

[tsedge]

They are not sealed units and the condensation behaviour is normal although undesirable.

 

[nexia201]

They are not sealed units and the condensation behaviour is normal although undesirable.

But seem to be hit or miss , the demo car i got did it , my car which i wash every 2 days with power wash and almos sometimes 4 days in a row in winter dont get it

 

[TC Electric]

Got my new MG4 Wednesday. Drove it through heavy rain first day, and lighter rain on Thursday and some on Friday. On Saturday the sun came back, and the fog problem revealed itself to me inside the left back light. Not much, but it's absolutely visible. Taking the car straight back to the dealership on Monday demanding them to repair it.

I have now read most of rhe threads on the "tailgate and back lights moisture fog problem". It's mind bothering how many people are persuaded by their dealerships, that this is a "normal and acceptable" issue. NO IT IS NOT! No car lamps are supposed to be taking in water. And cars are meant to be resistant ro rain, snow, heat and freezing temperatures. If a lamp can't withstand rain or a gentle wash, it is of poor quality or malfunctioning. As long as people are not delivering complaints, the issues will never be fixed addressed and fixed by SAIC.