yeti Leaking Panoramic Roof - The Cause and the Cure

[muppix]

4 minutes ago, stephmobile said:

I used bike frame protection tape from Amazon

 

Good to know, thanks! I did have a look on Amazon for that kind of thing, but there seems to be a vast selection of products with many different reviews, which makes me think that product market is rife with knock-offs. I don't suppose you could ping me a link to the product page? Do trim out any non-essential URL parameters which Amazon probably use for tracking ...

[Stubod]

https://www.amazon.co.uk/25mm-Bike-Frame-Protection-Tape/dp/B09J3TYHGL

 

..this could be it??

[stephmobile]

I used MTB Protex. I initially used 40mm but that is too narrow to cope with the curved corners, 100mm is better.

 

[Weti]

Hello,

I’m new to the forum but have tapped in to many other discussions for various reasons. 
 

I have owned a pano L&K Yeti for getting on for two years and obviously I have a sunroof leak. Why else would I be here…
Like others, I have common symptoms: lots of water in OS F&R footwells, wet around OSF curtain airbag, surface corrosion on fuse box. All drains are flowing water freely when poured directly into them but cannot see any source of free flowing water in the vehicle regardless of sponging endless amounts of water from the insulation. I guess the trickle is slow and constant and signs disappear quickly once the source (rain) stops. 
 

My questions to those with experience (apologies if this info exists within this chat but I did spend hours reading this page and other forums over the weekend) - for those who have paid Skoda for new sunroofs, new seals, new drains - have the problems resurfaced? Was it worth the repair? I would feel less bad paying for a repair with the knowledge the issue isn’t just ticking away again. I would now prefer to have a model without a sunroof but have a well-specced low miler and would actually like to keep it. 
 

I’m trying to drop the headlining but am struggling with the section with the sunroof controls and reading lights. Do these controls belong to the car or the headlining and if the latter, how do you continue to open/close the sunroof once detached?

 

Any pointers on how to remove the arm rest centre console up to the gear stick? The only fixing points I’ve seen on this are the two screws in the rear ashtray. 
 

The former owner appears to have a dog guard fitted in the luggage compartment. The guard is no longer present but the mounts are. Does anyone know how to remove the mount on the headlining above the rear-most side windows as these won’t simply pull away like other fixtures. 
 

I’d read in another discussion that removing front seats would trigger a dashboard fault. When I discussed this with main-dealer, they advised there wouldn’t be a fault provided the ignition was not on when the seat was out. When I refitted the seat to drive the car, the check engine warning light remains on. I’m not concerned as I’ve only removed the seat but don’t know why this has illuminated. Is this common following seat removal? The clock and economy data was also erased so it seems the module under the driver’s seat is integral to those systems(?)

 

TIA

Weti

[pinkpanther]

On 23/10/2023 at 11:20, Weti said:

Hello,

I’m new to the forum but have tapped in to many other discussions for various reasons. 
 

I have owned a pano L&K Yeti for getting on for two years and obviously I have a sunroof leak. Why else would I be here…
Like others, I have common symptoms: lots of water in OS F&R footwells, wet around OSF curtain airbag, surface corrosion on fuse box. All drains are flowing water freely when poured directly into them but cannot see any source of free flowing water in the vehicle regardless of sponging endless amounts of water from the insulation. I guess the trickle is slow and constant and signs disappear quickly once the source (rain) stops. 
 

My questions to those with experience (apologies if this info exists within this chat but I did spend hours reading this page and other forums over the weekend) - for those who have paid Skoda for new sunroofs, new seals, new drains - have the problems resurfaced? Was it worth the repair? I would feel less bad paying for a repair with the knowledge the issue isn’t just ticking away again. I would now prefer to have a model without a sunroof but have a well-specced low miler and would actually like to keep it. 
 

I’m trying to drop the headlining but am struggling with the section with the sunroof controls and reading lights. Do these controls belong to the car or the headlining and if the latter, how do you continue to open/close the sunroof once detached?

 

Any pointers on how to remove the arm rest centre console up to the gear stick? The only fixing points I’ve seen on this are the two screws in the rear ashtray. 
 

The former owner appears to have a dog guard fitted in the luggage compartment. The guard is no longer present but the mounts are. Does anyone know how to remove the mount on the headlining above the rear-most side windows as these won’t simply pull away like other fixtures. 
 

I’d read in another discussion that removing front seats would trigger a dashboard fault. When I discussed this with main-dealer, they advised there wouldn’t be a fault provided the ignition was not on when the seat was out. When I refitted the seat to drive the car, the check engine warning light remains on. I’m not concerned as I’ve only removed the seat but don’t know why this has illuminated. Is this common following seat removal? The clock and economy data was also erased so it seems the module under the driver’s seat is integral to those systems(?)

 

TIA

Weti

Sorry to hear you have fallen victim - a leaking pan roof was the reason I parted with my most recent Yeti.

 

Possibly worth talking to these guys?

 

https://www.thevehiclerepairspecialist.co.uk/sunroof-repair.html

Edited 24 October, 2023 by pinkpanther

[Weti]

Thanks @pinkpanther. I have had quotes from Mitchell Skoda in Chester who volunteered they’d had a fair few in for repair and no one back to complain following their repairs. 
 

I’ve read this thread from start to finish and am amazed that so many people and cars are affected. Top end Audis, lovely Passats and humble Yetis. VAG are a disgrace for continuing to fit these in much more recent cars given there were so many people complaining when this thread commenced 5 years ago. 
 

I have started to make comments on Skoda’s social media advertising so prospective buyers can get a feel for how we have been treated and how they might be treated if they have similar issues in years to come. Like others have mentioned, I’m surprised there has not been class action taken against VAG regarding this. Social media is a tool we’re all armed with though so I invite you to search out recent comments on SkodaUK’s Facebook profile and share your dismay and like my and others’ posts who are suffering these leaks.
 

So far they have been as useless as they’ve shown historically. They display public sympathy, inviting you to share your contact details so they can follow up with you by DMs. They simply ignore you. I respond to their messages on their main posts in full public view.  

 

On my initial post, I forgot to add: more of the common symptoms for me. I also get the glugging/gurgling sounds with the fan speed which stop when any door or window is even slightly opened. I find this most bizarre and wouldn’t have expected such a good pressure seal from a car given it has ventilation to the outside. The glugging sound is somewhat similar to the sound heard when you test the drains for flow. 

Although the drains do flow water, I suspect there is some restriction or hold up as a free-flowing pipe should allow water to pass with ease and no sound. Glugging indicates gas is flowing in the opposite direction (like backflow past a U bend) which should not be the case with an open system; (unless the water begins as a slug and transitions to annual flow (this would not be surprising given water’s high surface tension).
 

Where do the rear drains exit too please? Having crawled under the car, I can see they dump the water forward of the rear mudflaps but it’s difficult to see the actual exit location. 
Even though they’re flowing, I’d like to get a small bottle brush inside them to see if that alleviates the amount that comes inboard.

 

To those who have removed headlinings, what is holding up the sunroof and reading light controls? I’ve only removed the OS sun visor and driver’s grab handle. Do I just need to remove the NS to get better access? 

How do you remove the centre console up to the gear stick? Mine is a DSG. I’ve seen the removal of manual stick trim which looks easier as the gearstick gaiter is soft fabric opposed to the hard cover of the auto box stick. 

 

Anyone had any joy accessing the rear drains? I presume you have to remove the wheel arch liners to see them?

 

I’m not sure I agree with the OP regarding not blowing warm/hot air to dry surfaces. He proposes warm air holds more moisture (true) but warm air will also evaporate moisture off the surfaces you are trying to dry. Think of drying your hair; you don’t warm the room up by hair drying but you do dry your hair. 

Given the time of year and recent rainfall, I will be trying a hairdryer once I get the headlining out of the way.

Re Captain Tolleys, as it is a water based product i.e. the polymer active is suspended in water, it should not matter if the surfaces are not fully dry, as you are mainly introducing more water as you apply the product anyway. It will however mean longer drying times.

 

I guess I have been somewhat fortunate as I found water on Saturday and saw droplets from the cassette overlap on Tuesday. I was never happier to see water leaking into the car 🤣. Until then I was unsure if it was from behind the dash (windscreen etc). 
I have also seen water in the form of condensation on the aluminium rails which is most likely because the carpet is still very wet but the upper surface is cold. As that condensation collects and pools on the underside, it can also drip so it’s quite important to eliminate what’s lurking in the soundproofing. 

 

[Weti]

@muppix Do you still have your Yeti?

How are you getting on with your ingress? Is it fixed or ongoing?

I appear to be the first poster of the rainy season so after some dismantling advice…

 

You appear to have stripped your interior to get to the cassette. Please could you give me some pointers with regards to getting the headlining down sufficiently?
I have removed the driver’s side sunvisor and grab handle and detached the A pillar cover to reveal the curtain airbag and drain tube. Also removed the headlining from the fixtures all the way to the rear quarter panel window so can see above i t at the driver’s seat where my leak is. I don’t want to apply too much force though but would like to get better access to effect a repair. 

 

If you peer in from above the headlining at the sunroof controls, you can see what appears to be mountings just back from the windscreen but nothing corresponding on the underside of the lighting cluster/sunroof control panel to unscrew.  Do you pull that panel apart to access screws or does it come down on the headlining once the sun visors are removed on both sides of the car?

 

I don’t think I’ll be able to remove it entirely as the are dog cage mounts in the rear which hold it in place. I’ve no idea how they are attached.

 

Thanks,

Weti

 

 

 

[Stubod]

...you fail to realise that this is most deffinately NOT a design or manufacturing fault.....therefore it MUST be a user fault????

 

Hence after 20 years I will NEVER buy a a VAG car again......

[Weti]

Stubod,

Let’s get this message over to Skoda on the socials. Find the recent FB posts and post your feelings about it along with mine and hopefully others. Tell them they’ve lost your confidence as a buyer.
 

Only with the weight of our combined voices will we have an affect. Moaning amongst ourselves on here will do nothing.

Weti

 

 

 

[muppix]

11 hours ago, Weti said:

Do you still have your Yeti?

How are you getting on with your ingress? Is it fixed or ongoing?

 

Ongoing I'm afraid. I originally tried to fix it (with the roof lining in place) by replacing the boots that connect the drain hoses to the cassette, but when that didn't stem the flow I removed the headlining altogether and applied the recommended crack sealant to the areas where the different parts of the cassette meet up. I left the headlining out at that point because I wanted to be sure that the fix had taken, and almost 2 years later I'm still getting occasional dribbles here and there. The next step will be to take the cassette out completely and disassemble it, sealing it properly piece by piece on refit. I'm in the process of sorting some workshop space over winter so this may be a project when the evenings draw in.

 

11 hours ago, Weti said:

Please could you give me some pointers with regards to getting the headlining down sufficiently?

 

There's a PDF floating around on this forum which I followed without too much issue, and I'm glad I did because some of the things you need to remove - sunroof controls for example - are not straight forward, and it really helps to see where the fasteners are located beforehand. I thought I'd saved it locally but I'm not able to put my finger on it now - have a scratch around and I'm sure you'll locate it. Whatever it takes, I recommend taking the headlining out in order to do any work as otherwise you'll only end up damaging or marking it otherwise.

 

12 hours ago, Weti said:

Social media is a tool we’re all armed with [...] Let’s get this message over to Skoda on the socials. 

 

Social media is a way of monetising your life for the benefit of a handful of morally bankrupt companies. VAG don't care about the opinions of those with enough spare time to moan on FB all day long - they merely acknowledge you in front of other moaners by responding with a standard fob-off comment. Please use independent platforms like this forum whenever possible. 

[rover220]

11 hours ago, Weti said:

Stubod,

Let’s get this message over to Skoda on the socials. Find the recent FB posts and post your feelings about it along with mine and hopefully others. Tell them they’ve lost your confidence as a buyer.
 

Only with the weight of our combined voices will we have an affect. Moaning amongst ourselves on here will do nothing.

Weti

 

 

 

Yeah that will surely show them. 

[Weti]

I have taken a different approach to a repair, which has shown to be somewhat effective under controlled conditions - cheap, and not a drop of Captain Tolleys in sight. 
 

After some head scratching, I managed to remove the headlining and clean up the roof channels on both sides. 
Although I saw a drop of water on the underside of the cassette a few days ago, it was only one drop and I wanted further convincing where the leak location was. How a single drop translated to a flooded floor pan did not add up.

I dammed both the OSF drain hole on the cassette and the front lateral section and filled the front corner with water so the plastic-aluminium joint was fully submerged. There was no indication of a leak from the jointed section. As others have suggested the frame is weak and can flex when pushed from beneath, I applied a little pressure to the overlap from below but still nothing. 
 

I’ve been puzzled by the irregularity others have described trying to correlate rainfall (or lack thereof) with leaking. It would seem if that jointed section is fully under water, it will never see more water than that, has minor hydrostatic head pressure and should leak. Given it doesn’t, Are we really looking at the right point of ingress?
 

Anyway, I continued to slowly pour water into the dammed corner until it finally poured into the cabin. Thankfully I had prepared the seat for this as it was free flowing. 
Water exited from the usual place others have highlighted - the rectangular slot and opening above the worm drive (image below).
 

Considering I thought the corner I had dammed was enclosed plastic, I was curious as to the communication to the holes below. 

There is a huge gap between the outer sunroof seal and the plastic front tray where the cotton bud is inserted (image). Water can obviously pass through here very easily and is more in line with what I expected to see given the depth of water in my footwell. The plastic tray should never be that full though, and since the drains flow well enough. I remained puzzled as to how it entered the cabin. 

 

Finally with the roof closed, and the headlining out, whilst wetting the front of the sunroof, I managed to see water pouring in. It came down the gap with the cotton bud inserted, not the joint everyone has tried to seal with Captain Tolleys.

When wetting the roof, there was ingress at the front (and possibly rear) aspects of the outer sunroof seal. When water passes the seal, it should run into the plastic tray and down the tubes. No prizes for guessing where it actually goes…

 

There is a skirt on the same seal similar to a shower screen seal, which is supposed to guide the water into the tray. However it sits forward of the tray with no overlap. Water passing the seal of the closed roof is capable and does flow directly through the rectangular slots in the first image (there are two slots per side but only one is shown here).

 

Since I found a leak which flows into the car with the roof closed, when a relatively small volume was sprayed over it, I think it was reasonable cause to fix that and ignore the plastic-aluminium joint. 

Considering the size of the gap, there’s no way you’d seal it up. This needed a different approach. I was thinking roof tiles. Not literally, just the principal. To give the water a helping hand into the tray. Since I wanted my roof tile to have no - to minimal interference with the operation of the roof, it needed to be ultra thin yet water proof. 

 

Off I went to buy a bicycle tyre. £4. I was thinking narrowest but largest diameter, so a road bike/racing tyre. 
 

I sectioned the valve out, then gutted the remain tube so it opened flat. I inserted this under the sunroof seal, lapping it over the lip of the metalwork and into the plastic tray. 

Although the gaps I was trying to bridge were only at lateral aspects and whilst the factory seal overlapped much better in the central position (above the rear view mirror), I decided to fit a full length of rubber as it would be less likely to move around than two independent sections.

 

Given the amount of excess sitting in the gully, I cut it in two so I had two long strips. That would allow the wind buffer to fit back and not trap water on the underside of the tyre. I neatened the ends so the didn’t interfere with the guide rails and opened and closed the roof a number of times. There was no movement which might lead to it moving out of position.

 

Time to test the water - literally 

 

Sunroof closed, I gave the area a proper soaking with a specific focus on the entry points of the roof seal I’d found earlier. Nothing came into the car but a trickle was exiting at the designed exit points behind the doors. This was encouraging. Opening the roof again revealed additional trickles on the rear facing aspect of the tyre. This is the water that would ultimately find its way into the car during any rainfall. 
 

 

I’ll keep the headlining out for a while to check on progress but there was nothing following the evening rain that followed. 
 

So, if you have tried sealing the OP’s suggested joint area and had no success, give this technique a whirl and let me know how you get on. It’s about as a cheap a fix as you could ask for (about 1,000 times cheaper than main dealer!) and doesn’t actually need the headlining removing. 

 

I have cleaned and dried the OP’s joint too and will add some Tolley’s as I have seen moisture in the joint. 
 

A note on drying the area, I found using a pick and paper tissue to soak the water out of the joints works really well. The smaller the piece of tissue the better. If it’s double ply, separate it. Aim for an area of tissue about the size of your little finger nail then poke it in. Remove it and repeat. It’s surprising how much continues to come out which corroborates what everyone has remarked upon whilst adding Tolleys to the joint.

 

Weti 

[J.R.]

A man after my own heart 👍

[J.R.]

Would the inner tube flashing get sucked out while driving with the roof open?

 

Not insurmountable for a man with your fault finding logic and ingenuity but something to consider.

[Weti]

@J.R.no, it’s a small section and held firmly in place by the roof seal. The part exposed protrudes downwards into the plastic tray.

Additionally, given the profile of the inner tube is only ~0.5mm thick, it has minimal impact on the way the other seals and mechanicals of the roof, and wind buffer function. 
 

Not sure why I referred to it as a tyre in my previous post. It is clearly an inner tube. 

 

 

 

[J.R.]

I realised it was an inner tube and that you had even gone to the trouble of finding the thinnest, I did not have time to look at the photos in detail this morning as it was just before I left to meet the running group and I was in a hurry, unlike the internet connection downloading the photos.

 

Your description was very good though and painted its own picture!

 

Nice work, very satisfying 👍

 

I am treading a similar path on my actual house roof using similar lateral thinking, I have managed after a few failures that made things worse to resolve some chimney leaks (4 chimneys) that have been present for 60 years, now I am replacing roof timbers (rafters and purlins) from inside which was a similarl creative challenge.

 

Necessity is the mother of invention!

Edited 29 October, 2023 by J.R.

[Stubod]

..to be honest, given all these problems, VAG should have just offered a solid / fixed roof replacement that is permanently sealed in with the switch de-activated as a "low cost" alternative. Still gives you a "pan" roof but without the leak problems and would cost a hell of a lot less??

[J.R.]

Yeah, that could have been VAG's Ratner moment, just what they needed after  Emissionscheatgate!

 

How could it have been a lower cost alternative if it had all the same parts with additional sealing and a de-activated switch?

[BeePM]

 

I had the infamous sunroof leak suprise me about a month into purchasing my Yeti (only a couple of months ago). Luckily I purchased from a dealer so it was repaired under the warranty. Doesn't change the fact I now have a fresh anxiety kick in every time it lashes down with rain. As soon as the rain stops I'm straight out to check if there is any ingress into the car. So far so good, looks like the dealer has sorted it for now at least, but I still expect the worse that it will return in some form (sods law just after the dealer warranty expires). If it does leak again while under waranty I have told the dealer I will be returning the vehicle and will exchange it for one without the sunroof. A real shame that on such a fantastic car, Skoda dropped the ball on the most fundamental aspect of a version fitted with a sunroof ie. it being watertight.

 

 

On 28/10/2023 at 08:25, muppix said:

There's a PDF floating around on this forum which I followed without too much issue, and I'm glad I did because some of the things you need to remove - sunroof controls for example - are not straight forward, and it really helps to see where the fasteners are located beforehand. I thought I'd saved it locally but I'm not able to put my finger on it now - have a scratch around and I'm sure you'll locate it. Whatever it takes, I recommend taking the headlining out in order to do any work as otherwise you'll only end up damaging or marking it otherwise.

 

I saved both the pdf's I found on this in case I ever need them, I have added them here, all credit to the original creators.

 

On 27/10/2023 at 20:25, Weti said:

If you peer in from above the headlining at the sunroof controls, you can see what appears to be mountings just back from the windscreen but nothing corresponding on the underside of the lighting cluster/sunroof control panel to unscrew.  Do you pull that panel apart to access screws or does it come down on the headlining once the sun visors are removed on both sides of the car?

 

Because of my lack of faith that the leak won't come back at some point after the warranty expires, I have watched many videos on removing headliners to get an idea of what is involved. Although there aren't many videos specific to Yetis, I found the Tiguan videos (of which there are many, also the Jetta) to be a fairly similar process, enough to reassure me at least that it isn't as daunting as I at first thought.

 

Between reading the attached pdfs and watching the following videos it seems fairly straightforward to just unclip the Yeti's sunroof control panel and then unscrew / remove it if need be.

 

I hope they  give you an idea at least.

 

 

 

From 1.16 in this one

 

 

 

ATB / Bazza

 

 

 

Skoda Yeti Sunroof.pdf Yeti_Panoramic_Roof_Leak.pdf

[muppix]

4 hours ago, BeePM said:

Doesn't change the fact I now have a fresh anxiety kick in every time it lashes down with rain. As soon as the rain stops I'm straight out to check if there is any ingress into the car.

 

This may not do your anxiety any favours, but I found I had greater chances of water ingress if the car was parked facing slightly downhill. Might be worth your while forcing the issue, if you still have some warranty on your fix?

[Weti]

@BeePM do you know specifically  what your dealer fixed on your car? 
 

Anyone else who still suffered from leaks but has tried sealing the plastic-aluminium joint looked at the overlap of the front of the main seal into the plastic tray (the one I have the cotton bud in)? 

 

 

 

[BeePM]

7 hours ago, muppix said:

This may not do your anxiety any favours, but I found I had greater chances of water ingress if the car was parked facing slightly downhill. Might be worth your while forcing the issue, if you still have some warranty on your fix?

 

Agreed. Not the first time I have read / heard this and makes complete sense, especially if the issue is partially blocked drainage hoses / routes or leaking joints, which my issue appears to have been. Not only am I able to park on quite a steepish slope most evenings (plenty of hills where I am) but the car is looking lovely and clean because of the amount of pressure washing & car washes it’s been getting. I also park it nose up as well as nose down, to test both front and rear drainage routes. I had a long journey over the weekend, roundtrip of 400 miles and it completely lashed down both trips there and back. Although I found the driving in such torrential rain extremely challenging (most sensible drivers were reduced to 40 mph on the motorway, visibility was so bad) I tried to look at it as a good real-life test, and there wasn’t a drop in the car, so I’m fairly re-assured for now the dealer has sorted the issue, time will tell (insert fingers crossed emoji here).

 

1 hour ago, Weti said:

 do you know specifically  what your dealer fixed on your car? 

 

If the dealer is to be believed; it was the more common culprit of the drain hoses, where they join on to the collection tray spigots. I say ‘if the dealer is to be believed’ because the aftercare sales guy said there was a crack which needed to be sealed, but when I spoke to the actual mechanic carrying out the work, he said that it was the hose joints onto the tray. I also asked for photos to be provided before they re-installed the headliner so that I had an audit trail in case of future issues. Pictures added below of my initial discovery of the leak and where it showed itself, and also from the dealer showing the joints. They sealed all four joints (red hoses to the front, blues to the rear) . They allowed 3 days (allegedly) for the Skoda specific sealant (allegedly) to cure properly before water testing again and then returning the vehicle.

 

Do I come across as cynical in anyway 😁.

 

To be fair the dealers have been really good, I am so very glad we didn't go for a private seller. The warranty does offer peace of mind. If there is an option to extend it I will most likely take it.

 

Storm Ciarán tomorrow and Thursday should be a good test !

 

ATB / Bazza

 

Edited 31 October, 2023 by BeePM

[Stubod]

The problem I had with mine was the passenger side front drain pipe was "kinked". I took it into our local Indy and they replaced it. At the same time they "glued" all the pipes in place as they said that tended to be the main problem....ie the drain pipes coming loose and allowing water to run down the outside of the pipe into the car...

 

...NB I did not have a problem after this, but I decided to tape up the sunroof using clear gorrilla tap anyway, (just in case / paranoid), and obviously did not open the sunnroof again. Took the tap off when I sold it after 4 years....

 

Edited 31 October, 2023 by Stubod

[Weti]

I have finally found the cause of the gluggling/bongo drum sound from the rear of the car when the fan is on and the outside conditions are wet. 
 

A drain with a direct passage to the ground would not make this sound, and for a number of weeks I have thought it sounds like there is air trapped in the drains like a U bend. Even if the drains were partially blocked this sound should not occur. It can only happen if a liquid has the sort of non-continuous flow you get when pouring a full bottle of wine - the air stalls the flow of wine as it equalises the pressure in the bottle. If you were to pour a liquid down a section of tubing, even partially blocked, you will not hear the sound provided the tube travels continuously downwards. 
 

So, the cause is indeed a U bend effect. 
Take a look at the profile of the rear drain (blue pipe in image).  It runs downwards then back up before entering the enclosed box section behind the seatbelt. Since it falls and rises, water will sit in the low point.  With a positive pressure of air from the cabin pushing past it, the trapped water will make this sound. The only way to prevent it is to eliminate the rise and fall nature (though in reality it is fall and rise). This could probably be done by lightly strapping something slightly stiffer to the drain such as a thin section of wood or stiff plastic, so the drain always travels in a downward direct or at worst, only has level spots.  
 

 

Nobody has reported the sound coming from the front of the car, only the rear. This is because the front drains have a continuously falling profile. 
 

With the car standing for a week in the cold weather, I also noticed the roof, sunroof and windscreen were heavily covered with condensation. This presented as a combination of small and large water droplets which formed due to the vast amount of water still trapped in the car.  We all know condensation forms as humid air contacts cold surfaces (roof, sunroof etc). The aluminum sunroof channels of the cassette can also get cold and a provide a ‘good’ place for condensation to form. 
 

Since it only takes a few droplets to coalesce, a larger droplet of water can easily form and drip wherever this happens (usually from the aforementioned cold surfaces).  This can give the appearance that the car is leaking from places it actually is not. I believe this may be the case for many people who think their sunroof is leaking from the plastic-aluminium joint on the sunroof cassette. I myself saw water here and figured that was the point of ingress. The fact is, with enough water in the air, it can condense and drip virtually anywhere. With the headlining in place though, it will most likely run down the pillars making people think their drains or cassette is leaking. 
 

I you have tried to seal your drains or cassette without success, try the inner tube method I described above and see how you get on.

 

Below image shows excessive condensation with no leaking on or around the front drain hose or hose connection. 
 

[Grantola]

I've been following this thread for a while now and have tried many of the creative and appreciated fixes suggested by soggy-Yeti owners to date. To me, there's always been something fundamentally wrong that we've not identified as owners yet. My car has got progressively worse over time and the volume of water that's coming in to me implies a direct path, I suspect not (or in addition to) a capillary path. 

 

@Wetiwhen I read your post it made a lot of sense to me and hence I popped out this evening and fashioned the seals out of inner tube that you suggested, installed in mine. The design of the OEM seals really is crap as the whole thing depends on the drip pointing down the way otherwise the water is going to potentially run from the seal into that gap. The seals on mine have varible angles and I could see your hypothesis holding water (excuse the pun). Kudos for spotting it and providing this suggestion of a fix. I'll be delighted to test it.

 

I couldn't see how you'd got this concept to work with the sliding roof mechanism, so I simply ran the seal as far as I could around the front before it would start interfering with the roof mechanism. My leak is NSF.

 

While I was in there poking the inner tube in with a cake knife (the extant seal does seal nicely to it - nice thinking!), I spotted something. Has anyone considered the possibility of the wind deflector forming a structure to channel water from the area where it should drip into the tray to the inner part of the assembly? I saw that the inner plastic at the corner of the assembly was wet (highlighted in the image). The only way I could see water getting there was via the wind deflector. 

 

So I clipped out the wind deflector/fly screen (dead easy with flat blade screwdriver) and will try this in conjunction with the fix that @Weti has suggested.

 

It's been kept in the garage for the past couple of months, it is out in the Scottish rain tonight.