[voxmagna]

I'm a little busy at the mo. but have already posted info before (search?). The sunroof and window motors all have one thing in common. The amount of torque required to move the parts motors connect to is related to the d.c current draw of the motor. All motor controllers have V.W 'pinch protection' which disconnects motor power when a motor is stalled. The peak current point when it operates is preset by V.W in the motor controller. Pinch protection is also used to detect the physical end point stops of the operation - sunroof fully open or fully closed, windows fully up to the top seal, or lowered to the service position.

The window motor protection usually works well and you rarely hear of those motors or gears failing. However, the sunroof nylon gear has a reported high number of failures. In a good design the nylon gears should always be protected against excessive torque by pinch protection cutting in if friction on the slides or cables was too high. But it seems as though the pinch protection level they set is too high to protect the gearbox, or they cannot accurately rely on it due to the high mechanical torque produced on the output spiral 'worm' drive for the cable. Pinch protection operates with peak current. If a motor is run for long periods just below the protection point nylon gears won't be protected.

V.W should have designed the EOS sunroof motor gearbox to run reliably up to the preset pinch current. You will find most VAG sunroof motors are of a similar size and design to that used in the EOS and manufacturers have not redesigned the EOS sunroof motor. My guess is they used a standard motor assembly, realised the EOS Moonroof is much larger, heavier and with longer friction rails to move further back and modified the gearing ratios without considering the higher torque on gears using the same material? Count the tooth ratios on other similar VAG sunroof motors, or research the time taken for an EOS Moonroof to close compared to others cars. A slower heavier sunroof = more teeth on the nylon gear = higher tooth load.

Motor torque will depend on: Friction in the Bowden Octopus cables, the sunroof sliders, the weight of glass, torque required to close the sprung air deflector, and torque in the final stage of pulling down the sunroof to close until the motor stalls. I don't believe the Bowden Octopus cables are the culprit. From what little I've seen of mine, the inner is nylon turning in inside a nylon sheath, self lubricating. Therefore most friction requiring torque to overcome it, will come from the sliding sunroof?

Fortunately, you can easily get an idea of how hard the sunroof motor is working by measuring its running current during a sunroof open and close operation. The lower the current measured, the lower the torque required to move the parts. The approximate sunroof motor current can be measured in engine bay fuse slot F29 (50A) provide the roof pump isn't running. This lowest value with the motor removed from the cables running free should be about 1-2 amps. When the motor is driving the cables, an open sunroof should draw the least motor current as it starts to close from an open position. From memory it could be as low as 2-4 Amps? If it is a lot higher than this or stops on stall without moving far, then there's excessive friction. You then measure the current draw as the open sunroof moves forwards.

The current draw should stay fairly constant, but if it shoots up quickly at some point then that is a high friction fault either in the bowden cables or the sliders. If the motor current rises in a kind of linear fashion until the sunroof gets to the wind deflector and pull down stage, you can suspect the running guides may be out of square and tapered. When the sunroof reaches the wind deflector and pull down stage, motor current is the highest. I measured about 8-10 Amps (?). But that is a peak load only there for a few seconds in the last stage of closing. If the nylon gear were to fail for this short period peak I would expect to see 1 or 2 teeth broken, not all the teeth mashed up as in photos. My suspicion is all teeth mash up due to sustained continuous high load throughout most of the sunroof operation. You can repeat the current draw tests for a normally 'opening' sunroof. After an initial torque peak to lift the glass, current draw should stay as low as possible back to the normal fully open position. This position is not determined by motor stall current and the current draw should drop to zero when the motor stops. When a roof operation is in progress, the sunroof moves further back to hit a physical stop when the motor current rises to its preset stall value, then cuts off.

I have mentioned two possible causes of excessive friction - the static sliders and the Bowden Octopus cable. When the sunroof tray is connected to the cables you cannot move it by pushing due to the 'worm' gear design between the cables and the tray. To investigate sunroof sliding friction you would have to first disconnect the Bowden Octopus cables at the tray end. Alternatively, you can carefully use a key tool to manual open and close the winder at the end of the motor. But this is fraught with a gotcha! The gear shaft forming the key socket is soft muckite and easily rounded off. Also it is 'locked' and won't rotate until pushed down. Forget that without pushing down and the motor gear will appear seized, nothing moves and you risk damaging the soft key socket. Once you get over that hurdle and can manually move the sunroof you can get a feel for how much torque you are putting on the tool to get the sunroof to move. You should manually test move the sunroof all the way to fully open and back to closed, because as I explained, excessive friction may be in one place or increasing rapidly due to guides being tapered and not square.

For those spending lots of money at a workshop to get this problem resolved, their simplest approach is to replace the sunroof motor costing a fortune and grease the slide rails. But they are probably not checking the frame alignment using V.W service tool VAS 6370 (I have one!) or motor current and torque so you can't be sure their expensive fix will last. From this post you should have learned that measuring the sunroof motor current (or window motors) is a fairly easy non invasive way of monitoring health and keeping friction low. Another thing you can do is manually pop the wind deflector down before closing the sunroof to reduce torque loading in final pulldown stage.

The only permanent fix for the EOS sunroof motor problem is regular checks on the motor gearbox load or a gearbox with higher torque handling and more sensitive pinch level protection to warn of increased friction. I haven't looked closely at how V.W design the sunroof sliding rails. ABS plastic is poor and not self lubricating. My design choice would be ptfe if that were possible. To fix this problem forever, we need ptfe sliders, brass gears in the motor geabox and preferably motor current overload that operates sooner than pinch protection.

There is another EOS 'Bad Boy' I forget to mention. The sunroof tray has a blade either side that separates the roof seal. This metal blade has some kind of black surface paint that can wear (look at yours) but it is not very slippery and can add to the total friction if it's not lubricated. IMHO this should have been harder polished stainless steel or chrome, but it is what it is. Lubricating the roof seals helps for a while but I find myself adding lube if the seals start to pucker up as the sunroof is closed.

Happy New Year to All.

 

[eos2006]

Hi Voxmagna

Happy New Year to you too. Thanks for the detailed reply. I don't have the meter to check and probably feel a little out of my depth with anything electrical. Mechanical stuff I'm ok with. I guess you have answered one of my questions already:

"I have mentioned two possible causes of excessive friction - the static sliders and the Bowden Octopus cable. When the sunroof tray is connected to the cables you cannot move it by pushing due to the 'worm' gear design between the cables and the tray. To investigate sunroof sliding friction you would have to first disconnect the Bowden Octopus cables at the tray end. Alternatively, you can carefully use a key tool to manual open and close the winder at the end of the motor. But this is fraught with a gotcha! The gear shaft forming the key socket is soft muckite and easily rounded off. Also it is 'locked' and won't rotate until pushed down."

When I dropped the sunroof motor the external gearing had some debris around the cog teeth. I imagine that was the cable wearing away? Or is there a 'female cog wheel' in the roof mechanism that the motor external cogwheel couples with?

I took a couple of videos of my findings which I have posted online. It looks to me that just the white plastic wheel has worn. The spindle and outer wheel look ok. They don't appear to have any broken teeth. The runners look greased and clean from what I can see from the inside. The cables above the runners look clean, free from corrosion. Is there anything else I should be looking at?

 

[voxmagna]

I assume first that debris came from the nylon cog teeth that got munched? Without understanding the reasons and trying the motor current tests I suggested, you won't know a lot more until the new gear fails if you get the motor to run.

Alternatively for the mechanical minded you would have to try and test each part separately for excessive friction or binding. To do that you would have to disconnect and remove the Octopus cable. Then you should be able to try sliding the sunroof, the motor and new gearbox should be o.k so you are left with the Octopus cable and 'transfer assembly' in the center.

From what little I've seen, the ends of the bowden octopus cable inner have a coarse spiral wire which replicates a worm gear. If you look at slots the sunroof tray runs in you can see a similar thing. I suspect there will be a nylon or metal 'slipper' that uses the cable ends like a screw thread. As the Octopus cable turns, it winds the slipper carrying the sunroof frame forwards and back? If I am right about that, excessive force due to stiffness could change the pitch of the spiral on the octopus cable inner. Worse case with large twisting forces, the wire turns could close together, bunch up or even break away loose. The internally threaded slipper won't run smoothly over them and seize. If that happens you will have to replace the octopus cable assembly after checks on free movement of the sunroof in its guides. Threads in nylon are easily damaged. But if the slippers are steel not softer brass, they won't self lubricate. These are guesses as to how it works & I could be wrong! One trap to fall into is to try turning the octopus cables once disconnected at each end. But remember they turn and twist against large forces which you cannot now replicate. You may be able to visually check the ends, but won't see what's going on inside the sheath on the bends.

You will have to remove the headlining and investigate why there are 8 cables (push-pull?) what's driving what and in which direction. Greasing rails doesn't sound to me like the only thing you can do if there are slippers moving along the cable? You are well placed to do a write up with photos to tell Members how it all works and what goes wrong.

I've read this before, but I'll post it for you:

The sunroof motor is equipped with a closing force limit. If the roof runs into an obstacle during the closing procedure, the motor stops and the glass panel moves in the opposite direction.

‹› If the glass panel is closed a second time with the switch, it runs with increased closing force. If the glass panel still runs into an obstacle, it runs once again in the opposite direction.

‹› If the glass panel is closed a third time using the switch, it runs without a closing force limit.

‹› All screws are microencapsulated and must always be replaced

As you can see, even V.W appear to say the sunroof mechanism can self destruct (expensively).
If the glass panel is closed a third time using the switch, it runs without a closing force limit.

I was right about pinch protection, but this explains why the nylon gear might self destruct after 2 attempts - because they disabled pinch protection for reasons I do not understand?

If you don't dismantle parts and find the friction problem, your new gear after two strikes might fail like the other one?

 

[eos2006]

I assume first that debris came from the nylon cog teeth that got munched? - Just went out and took another video. Looks like the debris came from the cables/external cog (combination of both probably. However, as the cables have now been moved when the sunroof was closed manually, I can't see the wear in the cables. Also, a have-a-go-hero like me would look at the external cog and internal drive cog and deem they looked fine. I wonder if an engineer would take one look and say they were fubar?

From what little I've seen, the ends of the bowden octopus cable inner have a coarse spiral wire which replicates a worm gear. If you look at slots the sunroof tray runs in you can see a similar thing. I suspect there will be a nylon or metal 'slipper' that uses the cable ends like a screw thread. As the Octopus cable turns, it winds the slipper carrying the sunroof frame forwards and back? - That seems correct. That would explain why each cable has a casing that runs past the main drive. So in fact there are only 4 cables, not 8.

You will have to remove the headlining and investigate why there are 8 cables (push-pull?) what's driving what and in which direction. Greasing rails doesn't sound to me like the only thing you can do if there are slippers moving along the cable? You are well placed to do a write up with photos to tell Members how it all works and what goes wrong. - As mentioned, there are only 4 cables. Very hard to see how and where they attach to but looks like 2 cables pull the glass and the other two the sun visor (I could be wrong. Will double check in daylight.) Removing the sun visor looks like a world of pain, yet alone the cables.

I did move the sun visor back and forth. It moves pretty freely. I can't see an obvious way you manually move the glass though. If I could then that may highlight where the resistance is happening.


I've read this before, but I'll post it for you:

The sunroof motor is equipped with a closing force limit. If the roof runs into an obstacle during the closing procedure, the motor stops and the glass panel moves in the opposite direction.

‹› If the glass panel is closed a second time with the switch, it runs with increased closing force. If the glass panel still runs into an obstacle, it runs once again in the opposite direction.

‹› If the glass panel is closed a third time using the switch, it runs without a closing force limit.

‹› All screws are microencapsulated and must always be replaced

As you can see, even V.W appear to say the sunroof mechanism can self destruct (expensively).
If the glass panel is closed a third time using the switch, it runs without a closing force limit.

I was right about pinch protection, but this explains why the nylon gear might self destruct after 2 attempts - because they disabled pinch protection for reasons I do not understand? - Thinking back, I think this is what happened to me. My roof was having issues going back in to place. I do recall the sunroof moving backwards, but then coming back forwards a few times and then it went backwards and came off the rail. I guess that was the point that the pinch point was disabled.

If you don't dismantle parts and find the friction problem, your new gear after two strikes might fail like the other one? - Quite possibly. But I can't see a way to single-handedly get the sunroof opened so I can check all the channels and tracks. I've ordered a replacement inner cog wheel (plastic, not the brass one that is available). When it arrives I'll take a shot at trying that out. Lord only knows what other damage the guys at the Stealership did when they forced my sunroof closed. Its a £30 punt. You never know - I may get lucky. Though the way 2021 has started I fear the worse.

With regards to cleaning out the channels, I assume that needs to be done from within the car. What is the best way to clean them out? I could clean these channels out and try inject grease back in to the tracks. As for cleaning and greasing the cables, how is this done?

Took another quick video. Excuse the shakey-cam - It's a tricky position to try video.

 

[voxmagna]

So far we seem to be on the same page, even though some of my comments are guesswork. I didn't think the sunshade was connected to anything? I though it floated free and was pulled back by the sunroof glassor pushed forwards with it, but they could use slippers on cables. Theres no hard connection it seems so it could be a simple push-pull action? The sunshade should move very easily and not contribute that much friction.

I was looking at some cable assemblies for sale on Fleabay. Check out their photos:

VW EOS 2006 - 2016 roof guide unit 1Q0871407 New genuine VW part for sale

Find many great new & used options and get the best deals for VW EOS 2006 - 2016 roof guide unit 1Q0871407 New genuine VW part at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

It looks like there are 8?

As I've already said, you cannot move the glass until you disconnect the octopus cables from it because they are the worm drive. Forcing the glass closed is impossible and will damage the octopus cable drive. That's why V.W included the manual turning on the gearbox. But if there is serious seizure, that won't work.

Yes, removing the sunshade and the getting access to the sliding roof is a pain and why Stealerships avoid it or charge a lot of money. It's the same problem for anybody with a sun damaged or torn sunshade - a major job to replace it. I can't remember but I think you may be removing the roof top sections for access and will enter a new world of aligning the sunroof tracks and special service tools? But I don't think you have any choice because it doesn't look like a simple squirt of lube is the fix and you may now be looking at replacing a faulty cable asembly. You may have started with stiffness or friction but now after 2 strikes on the button the whole mechanism may have more damage. If you haven't got a paid for workshop manual download I think you will need it?

Lord only knows what other damage the guys at the Stealership did when they forced my sunroof closed

They did what was easiest. Instead of going for a dismantle immediately and a big bill, they used the emergency close with a key in the motor. This would need a large force on a sunroof already jammed. That would cause or hasten failure of the gear teeth because I think the damage was already caused by the seizure made worse by emergency manual closing. But short of a tarp over, what were they to do?

In your next reply we expect to read you have bitten the bullet, disconnected the octopus cables from the sliding glass and motor, even removed the frame and have done a thorough test and inspection looking for the problem to post a full write up and photos? If you replace the octopus cables you can cut the old cable assembly open with a disc cutter and take photos.

 

[eos2006]

Hey Vox,

Morning mate. Afraid you are gonna have to lower your expectations

Looks like 8 cables:

But in reality, only 4:

Interesting thing about the cables, I've spotted a couple of ads now on Fleabay for the cables casings but none of them have the actual cables. Even the one you posted states:

"Item description

This is a roof brace kit/ guide tube for the Cabrio Roof it is not the roof cables.

It is for the following vehicles:

Volkswagen

EOS 2006 onwards"

So that would imply they are available separately. Assuming so, surely in 10+ years of this forum someone has taken on that task and posted some evidence?

Looking at the parts available though I don't see the cables:

RETRACTABLE TOP. FRAME & COMPONENTS.. Volkswagen Eos

Volkswagen Eos RETRACTABLE TOP. FRAME & COMPONENTS. 1. 5MM. 1MM. From 09/2008. From 10/06/2008. To 08/2008. To 10/03/2008.

parts.vw.com

Someone else is selling a roof "with defects" (surely the defect is "where's the rest of the car?")

I was hoping to see if there was any obvious way from photos to tackle this. I have read so many threads on this forum about it, into the wee hours of the morning, but often the thread just stops; falls off a cliff; no more updates or photos/videos. Seems inconceivable that this task hasn't been documented...... other than in a workshop manual. Or maybe the cars are now of an age that this is only starting to happen over the past few years?

"That would cause or hasten failure of the gear teeth because I think the damage was already caused by the seizure made worse by emergency manual closing." - That makes sense. So that debris around the external gear was from the guys wrestling it closed rather than the motor trying to close it, you think? Maybe I should also buy a replacement outer gearing too and swap that out whilst I'm in there.

Anyways, am waiting for the internal gearing to arrive and will test the motor then - make sure its all running before I think about hooking it all back up. I'm still trying to understand why the channels for the cables can't be cleaned and lubed from the side on, rather than having to take the whole thing apart. If it ever stops raining/temperature gets above 1C and I can take the car out into the daylight I'll have a closer look and report back.

Cheers for now!

 

[voxmagna]

I already knew that 8 cables was a semantic description and since there is pass-through the center mount, it's in reality 4 cables. But 'octopus' is a good description making searching for info a lot more precise. To be more semantically correct it's 4 continous cables with 8 ends. but if you are going for the teardown and inspection as I suggested, it's the 8 ends and what happens inside on the bends that really matters.

I did think after your comment about the lightweight sliding sunshade tray, that 2 cables/4 ends would be a torque overkill to move that when I can easily move it with my hand even when driving and there is no resistance you would expect if there was a close coupled connection to the motor. However, pull down into seals on close requires the most motor torque which comes from the same cables moving the glass. Correction: 2cables/4 ends are close coupled to move the glass back and forth. raise and lower the glass. Whilst 2 cables 4 ends DO open and close the sunshade, but they are not close coupled to it because you can manually open and close the shade whilst driving Those cables shouldn't be working very hard hard if the sunshade can be opened and closed manually without much friction.

You have plenty of info now and even without a multimeter you should be able go further? If an Ebay seller can remove the complete assembly to list and sell, you should be able to do it. But without a shop manual you could easily underestimate the procedure to remove and refit correctly without getting sunroof seal leaks afterwards.

There is an incorrect assertion here that water drains below the sunroof seals 'normally' carry away water when there should be none with good seals. Any water getting past sunroof seals can get into the cable sliding mechanism. I suspect those that have had seized sunroofs have gone with lubrication and clearing drains rather than resolve sunroof seal leaks first? I have no water in my sunroof drains and if I get any I investigate the seals first. There's another source for water entering the sliding mechanism and that's condensation particularly for an EOS outside 24/7. Condensation is caused either by letting water from shoes, clothes etc remain trapped inside the cabin, or a seal leak that hasn't been discovered. On a cold damp evening or morning, wipe the inside of the sunroof glass to see how much condensation it can hold and how much water has settled on the cold steel sliding channels and cable spirals. If a thorough leak investigation has been carried out, leave a domestic compressor type dehumidifier on the seat for a few hours to dry out the cabin during Winter months. Repeat every 2-3 weeks if not driving the car.

Post your photos and procedure for the next active steps in your work. Finding photos from others doesn't always mean you have the same problem.

 

[eos2006]

Sir Yes SIr!

You are a tough taskmaster. You remind me of my old boss. He was an ex US Marine. Are you sure you are not actually Gny. Sgt. Hartman? 😁

"This is my EOS. There are many like it, but this one is mine.
My EOS is my best friend. It is my life. I must master it as I must master my life.
Without me, my EOS is useless. Without my EOS, I am useless. I must fix my EOS true. I must fix my roof straighter than my VW Stealership enemy who is trying to rob me blind. I must fix this roof before he invoices me. I will ..."

So, found this link. I ass-u-me this is the lesser spotted octopus cables? I thought they were all same part, regardless of year? (Mine is 2006.)

Volkswagen Eos Convertible Top Cable - 1Q0871327 - Genuine Volkswagen Part

Convertible Top Cable. Volkswagen Eos. Genuine Volkswagen Part - 1Q0871327 (1Q0-871-327)

parts.vw.com

 

[voxmagna]

You are just going to fall into big holes if you rely on an internet search and EOS year to get correct roof system parts. Most EOS parts carry their part number if you look carefully for them.

EOS roof parts, assemblies and changed parts can be specific to your EOS VIN. Unless you have access to the genuine Stealer parts list, I suggest you pay them a visit, whilst keeping your wallet at home. Give the parts guy your VIN number and ask them to confirm the EXACT part number (s), price, and availability. You will be glad you left your wallet at home! Your EOS build from new will be different to even the same model built a month later. From your VIN they can look up (but won't share), data on a complete set of parts fitted when your car was built. There are lots of copied non-genuine V.W parts with 'similar' numbers on Fleabay.

-- I've just been called up for a part in a remake of Full Metal Jacket.

 

[aku-aku]

Looks like you are right about the part number. You should consult the parts diagram though. Don't trust me - convince yourself based on the descriptions on the parts diagram!

 

[eos2006]

Thanks Aku-aku,

Thank you for the link to the diagram. I called the Stealership and had a good chat with them. Part 1Q0871327 is the cables for the glass sunroof (separate part number for the sun visor cables.) I asked him if it was common practice to replace both sets of cables when swapping them out. He said he rarely sold either set of cables. He sold ONE set of the glass sun roof cables all of last year. I'm in Cornwall and I've seen a lot of EOS down here so very surprising he hasn't sold more. £57.32 for pair of the sun roof cables in case you are curious

I mentioned I was waiting on a new internal gear wheel to try rescue the sun roof motor. They don't even attempt to fix the motors - only supply a whole new motor (£500!) What isn't clear from the diagram though is what part #34 is. He didn't know either. Is it the external gear on the motor or is this a separate gear wheel? I assumed the external gear wheel fitted up in to the cable casing and drove the cables back and forth. Is this part:

..... this gear wheel?

This gear wheel fits in to here:

I assumed what I was looking at in there was the cables. Do you guys know if that is the cables or is it a 'female gearing' and the cables run either side of that? I'm 99% certain it is the cables. My doubt arose because VW said #34 was only £11-odd but I've seen the external gear on sale on fleabay for £130 and as we know, they aren't called the Stealership for nothing!! Fleabay has that external gear as part number "1Q0959591 B C" which I don't see listed either. It's a bit confusing.

Final question for today .... lube!! VW want £45 for a small tube of lube for the rails. I've looked on a few forums and seen Superlube mentioned a few times. In your opinion would this be ok to use?

Vox.... I'm edging ever closer to taking these things apart - I promise. I just want to make sure I have as much prep done beforehand and all the bits I need to hand.

 

[voxmagna]

You seem to have reached the point where you have to do some teardown work? Even after buying what you think are the correct parts, you should compare new with old and make sure. I thought I'd explained the EOS sunroof cable and gear design as I see it? The simplest explanation is it works like rack & pinion steering. The angular rotation of a gear (straight cut or worm) is converted to linear push pull motion.

Your photo clearly shows this, although one side only. The gear sits in the cable spiral for BOTH cables. When the gear rotates clockwise one cable of a pair pushes and the other pulls. For reverse rotation of the motor and gear, the opposite happens.

Therefore, both spirals on the cable inners must mesh perfectly with the gear over the full movement range of the push pull cables. Just one photo snapshot doesn't confirm the condition of the spiral for the whole movement, or when under load- you have to determine that. If you can remove the cable inners you will have a better chance of inspecting the spiral tracks. BUT you have to put each back to the same point if re-using them. You must mark each spiral where the gear meshes or measure the end projection with a vernier before pulling out the inner.

All is not so simple because the spiral runs inside a (nylon?) sleeve and ABS housing at the critical central driving point in your photo, which could have worn internally where the motor gear meshes. If that happens, the spiral cable inner will push outwards away from the gear, lose mesh and the push-pull cable pair may lose length sync. Most likely is the motor may try to pull or push the sunroof on one pair of cables and there will be a 'click-click' as the gear is riding over the spiral of the second pair. Although the large heavy sunroof may still move, it is being push-pulled unevenly along one side and WILL jam in its tracks. As I have explained this, lubricating the sunroof sliders and the spiral is preventative maintenance only. But once there is wear at the star point, a jam or damage of the close mesh of one spiral cable, only one pair on one side will be moving the sunroof and the nylon gear is the weakest part to fail after 2 strikes.

It is widely reported on the internet that EOS sunroofs can be repaired by replacing the nylon gear and lubricating the sliders? But IMHO if the 'hidden from view' gear to cable mesh or spirals are stretched or damage, the sunroof may appear to work for a short time with one pair of push-pull cables meshed, but will eventually fail again. There won't be many EOS's sold in Cornwall U.K which has one of the lowest population densities.

What this means for you with all the information you have amassed is you may go the cheap route to replace the spiral cable inners, but overlook the possibility of wear or damage to the central star point where there are huge torques? I still think the highest loading cables most likely to fail will be for the sunroof. Once you realize how much time and work is needed to repair an EOS sunroof successfully to avoid going back, you might consider using your motor and new gear with new cables both outers and inners. You will need a workshop manual. If I was a competent Stealer repairing an EOS sunroof like yours & giving a warranty, I would replace the motor AND complete cable assembly. Cut corners and you run the risk of failure with a non-working hard top.

I don't know why you think the metal gear is bad unless it has lost/worn teeth or they are damaged?

This might seem a lot of money, but needs time and precision engineering to cut the gear correctly from brass. It would be my preferred solution, although I'd search wider for cheaper. Read what the seller says about the cables and guides, everything I said above!!

VW EOS Sunroof Motor Repair Kit - Internal Gear BRASS Upgrade - 1Q0959591 B C | eBay

Find many great new & used options and get the best deals for VW EOS Sunroof Motor Repair Kit - Internal Gear BRASS Upgrade - 1Q0959591 B C at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

 

[eos2006]

I bought and just received one of the plastic cogs though. Didn't go down the brass route. I figured these are meant to fail for a reason. They call out the cable issues on the bag for the cog too:

View attachment 22981

Registration < Volkswagen AG erWin Online - am stuck on Volkswagen OridID so can't register to download the workshop manual. Grrr.

Having a flick through this one instead.... though can't download it, which is annoying:

Volkswagen Workshop Manuals > Eos (1F7) L4-2.0L Turbo (CCTA) (2009) > Body and Frame > Roof and Associated Components > Sunroof / Moonroof > Sunroof / Moonroof Track > Component Information > Service and Repair > Interior Trim > Page 6442

Eos (1F7) L4-2.0L Turbo (CCTA) (2009) > Volkswagen Workshop Manuals > Body and Frame > Roof and Associated Components > Sunroof / Moonroof > Sunroof / Moonroof Track > Component Information > Service and Repair > Interior Trim > Page 6442

workshop-manuals.com

Have ordered some Superlube. If that arrives by Saturday then getting stuck in to this will be my weekend job.

Reading the workshop manual it says more than once "All screws are microencapsulated and must always be replaced" ...it seems VW have covered all the bases on making this hard to resolve yourself.

 

[eos2006]

 

[voxmagna]

"All screws are microencapsulated and must always be replaced" ...it seems VW have covered all the bases on making this hard to resolve yourself.

No they haven't. The problem is you expect everything to be written down for you and to find exactly the right information when you don't seem to have experience of working through technically complex V.W. procedures?

V.W often require screws and fasteners to be replaced because the original screws are either pre-coated with threadlock or use a special 'use once' torque procedure which stretches the bolt. I don't know what you are reading and I'm not going to teach you, but fasteners used as part of the roof structure can be special bolts, because the car might roll over and you don't want cheap re-used screws coming out and the roof collapsing on your head.

Why don't you use this site search more, instead of looking elsewhere? There are several 'private' websites already mentioned in previous posts which you can look at. Your problem is you thought you could buy a cheap replacement gear and fix your sunroof motor, when in reality a more complex expensive repair is required because the gear failed due to other causes. EOS sunroof repair work would normally be done by trained V.W roof technicians. You may have to remove most of the sunroof and roof top assembly to replace other parts, which is what I and the warnings from the gear sellers are telling you. I'm one of the few DIYers here that have been in the roof top sections and replaced them correctly aligned, but don't listen if you want to dig a bigger hole for yourself. The EOS workshop manual is not a precise set of easy to follow instructions for DIYers without experience and some things are missing which you have to work out for yourself.

Try talking to Cayman Autos who are independent cabriolet repairers who others here have used. If they estimate £1000+ for the sunroof parts and labor, that would sound about right for technicians who know what they are doing. In Tier4 Covid lockdown you are unlikely to be going anywhere at the mo. and Hampshire/Surrey have lots of traffic cameras.

Volkswagen EOS 2006-2010 repair manual | Factory Manual

The Volkswagen EOS 2006 2007 2008 2009 2010 factory repair manual it is the only service manual who cover all aspects in repair!

www.factory-manuals.com

 

[eos2006]

Little update on my issue. So I swapped out the inner gear on the sunroof motor, cleaned all rails and tracks, lubed anything I could get lube in to, cleaned all the tracks, moisturised all the seals and rubbers that i could force a fat finger in to and gave the sun roof a try. Roof slid back first time! In fact it was running better than it ever had. I opened and closed it about a dozen times. About 5 or 6 times it closed fully, then automatically re-opened fully, which was weird. There was nothing blocking it. I figured it was a reconfiguring/initialising thing and planned to check on the forum and go back to it tomorrow.

However, the idiot in me grabbed a hold of me and took over. So, I took the car out of the garage and tried the roof. Sunroof slid back without issue, everything folded as expected but when the main section dropped into the boot it made a bit of an unusual clunk noise. The roof finished closing all the flaps and the boot closed as expected and windows came up. The problem arose when I went to raise the roof. Windows dropped, boot opened, main section moved a bit bit then no more. On closer inspection it appears the sunroof is catching on a bolt on the back of the seats and not allowing free movement. At this point I have dropped the roof down again and put it in to the garage, to be examined in daylight. Strangely though, this problem rings a bell. I think I have read about this one on this forum previously. So tonight I suspect I shall be scouring old posts for the solution.

Onwards and upwards!

 

[eos2006]

Yup - found it:

EOS ROOF STUCK IN OPEN POSITION

When I opened the roof, as it folded into the boot there was a bit of a bang. I wondered whether I'd left something in the boot side voids (will the roof fold down if there's something in one of these side areas in the boot, ie. is there a sensor that prevents this from happening?) When I came...

www.vweosclub.com

And another one:

Roof Not Closing!

Okay so I’m having a bit of an issue! My Eos roof will go down perfectly no issues at all but when it comes to putting it back up it gets stuck in the boot of the car it looks as if the sun roof is catching on the rear seats and stopping it from coming back up! The only way I have been able to...

www.vweosclub.com

So looks like the sun roof didn't go all the way back...... fell short by a few cm by the looks of it.

Think I've gone as far as I can go with this. Need to find myself an independent VW specialist

 

[voxmagna]

More expensive consequential damage is a big risk when you attempt DIY work on the EOS roof. I did say you should check condition of the spiral mesh on the Bowden cable 'All the way along its full movement' which would mean the end to end stop of the sunroof? Either the motor controller isn't correctly reset or couldn't reset because the Bowden cable spiral was damaged at that point where it would have been fully extended and stopped short of reset to the correct value.

I assumed you would know that the sunroof had a calibration procedure same as the windows (all in the workshop manual and in this forum!) and would have done that before even attempting a roof operation? If you had done that first, you would have known the sunroof was not fully extending to the rear and something was wrong? It would also have told you that operating the roof could be a fatal operation because what was the roof system supposed to do with the package when the sunroof was not in the correct position?

You put in an aftermarket gear part and as I warned others in a previous post, the gear diameter and tooth count must match precisely for the pre-programmed controller software to calculate the sunroof distances correctly.

Normally the roof operation would abort and not advance to the next step of lowering the package if the sunroof was not in the correct full back position corresponding to the count it expected. My suspicion is your controller count thought it was in the correct place and allowed the roof operation to continue. It might do this if the spiral mesh was bad and the small metal gear jumped teeth on a bad section of the cable. This would be confirmed if you tried to close the sunroof and it didn't return to the fully closed and lowered position or returned and stopped in different positions each test operation. If the gearing ratio precision was wrong then after re-calibration I would expect the sunroof end position distance to be shorter (or longer?) but stop consistently in the same place each time. The controller thinks it has counted correctly, but the motor gearing ration isn't correct?

I've already posted something about checking the end to end rotation of the motor forwards and in reverse when it is removed from the sunroof. In my case because I'm careful, I got the sunroof fully closed first and with the motor removed from the frame, test ran it forwards and backwards to its extremes after following the calibration reset procedure, then the sunroof switch and finally back to the motor starting point and re-attaching it to the sunroof frame. This ensures the motor now having got and stored the correct end to end range count, is re-assembled with the gear and cable spirals at the correct starting point. This is my procedure not documented in the manual or posted on YouTube. There are no position sensors in the sunroof sliding mechanism!! It took 2 or 3 attempts to get this right. I had no gear faults, suspect damaged cables, used any aftermarket parts or uncertainty that a gear ratio might be incorrect. I had just removed the motor, had the sunroof 2/3rds open for a week or two with the battery disconnected.

If you go to a competent independent, you should be upfront and tell them exactly what you have done. Spring and warm days for top down driving are coming soon!

 

[eos2006]

Me again.

Top down driving I can do.... it's getting the bugger back up is the problem

I managed to get the roof back up quite easily. Looking at it in daylight I could clearly see the sun roof was catching on just the middle screw of the plastic panel behind the rear seats so I just removed the screw and guided the payload past that panel. The main roof section closed without issue.

However the sun roof is still intermittently bouncing back and forth. Listening to the mechanism whilst closing there is a point I do hear a very slight change of sound, which may well be a wear in the cables as you suspect. But the strange part of this behaviour is that it is not 100% consistent. On some occasions the roof closes as expected. On others it either bounces back to the open position (is it fully open? see 1:21) or it stops prematurely during the 'tilt close' procedure.

When I swapped out the inner gear wheel I did run the motor back and forth to it's extremes a number of times with the motor not fixed to the cables. It all ran smoothly. It's interesting that when the sun roof bounces back it does so at speed - a lot quicker than when it closes.

I noticed a cable end looks like it has become detached. It looks like a guide for the sun visor cable so I don't believe this is contributing to the issue.

With the windows down and sun roof fully opened I tried the convenience closing procedure. Windows closed as expected. Sun roof closed but bounced back to the open position.

I called one local VW independent garage. They had not worked on them before unfortunately. He actually wants to buy one himself and was very curious about what I had found thus far so had a good chat with him. I obviously warned him off buying one.

Just had a good chat with these guys. They have worked on these roofs before and happy to spend an hour trying to diagnose the issue. I explained what had happened to date and that I was looking for an economical approach to a repair, rather than a blanket swap out of all their parts and they are happy to do that. So, fingers crossed!!

 

[voxmagna]

By now should have read everything and taken it all in?

With the windows down and sun roof fully opened I tried the convenience closing procedure. Windows closed as expected. Sun roof closed but bounced back to the open position.

Didn't that tell you something? It did that because the fully closed position wasn't learned by the motor controller and the 'Bounce back' as you put it is V.W's pinch protection because the motor thought it needed to go further forwards than it should! If you understand what I said in my last post, I created my own procedure to check the motor would stop at each end then replaced it with the sunroof fully closed. Obviously when my ignition was first turned on the sunroof would be fully closed and if motored a short distance back on the switch, should move forwards to fully close without bouncing back as you put it - Unless the spiral was damaged and seizing at the maximum torque point where it goes to fully closed? Then pinch protection would operate. But all these things can be compounded by what you haven't done - dismantled to thoroughly inspect the cables and what you have done - fitted aftermarket parts to the motor- plus not understanding what to expect from 'reset' and how the sunroof knows when and where to stop.

IMHO if you take your car somewhere other than places where they have actually done significant work on an EOS sunroof and have an EOS trained roof technician on site, they will do an easy diagnostics scan, learn at your expense and guess at what's needed. Once they read the V.W workshop manual procedures for an EOS sunroof teardown, they will run a mile. If it's a genuine V.W workshop you will have a better chance because they will have direct access to the mothership for information. They will probably advise replacing the sunroof motor and octopus cable assembly with genuine O.E. parts. Good Luck.