Hi, all.

• 2008 S63 standard sunroof.
• Was opening the sunroof and heard a "crack" like plastic breaking.
• Sunroof would not move and is now stuck at this angle as though it is off of a guide. Note the unevenness at the back as the glass enters the roof as well.
• I found small bits of plastic under the corner that is lifted.

I'm assuming that I'll have to go from underneath and remove the headliner then remove the sunroof assembly. But, before I pull all of that down I figured I'd ask.

This person had the same issue, but no responses on this thread (except me asking for an update): https://mbworld.org/forums/s-class-w...-position.html

Any help will be greatly appreciated!

 

You have a manual open/close bolt near your visors. It's covered with a plastic plug. It's an allen headed type thing. My car came with the tool required for this. I hope yours did. If not, it's probably just a big allen. You can use it to wiggle the sunroof back and forth while guiding it with your hands. This should at least get it closed and buy you some time so you can order some sunroof rail guides. Also, get some Mercedes sunroof lubricant. The tub is horribly expensive but Mercedes parts houses will sell it in half ounce containers. A half ounce will last a long time.

 

Awesome. Thanks!

For the record, the motor seems to be functioning fine. It attempts to move the glass, but it seems to be jammed (or it's sensing resistance and stopping itself).

It seems to have jumped out/off of the track. Do you think that turning that bolt will get the sunroof to lay down and close?

 

You're going to need to guide it into place with your fingers. You really don't want to do that using the motor. If you feel binding, you can back it off a little and push in a different spot. It looks to me like you will need to push up on the front left part of the glass as you gently close it. You may need to open it a little bit first to get things to move when you push.

 

Sorry, I was backwards. You're going to need to push up on the rear right to get the front to sit down.

 

OK. Sounds like a good plan.

I'll try in the morning and report back.

Any suggestions on how to troubleshoot the issue and replace the broken parts?

 

No because I don't know what part broke. You can look around here--> https://mbparts.mbusa.com/ and match up the pieces that broke. If worse comes to worse, you can get the tracks, motors and everything on eBay for $500-$600. That's kind of the nuclear option though. I'd focus on the plastic.

 

OK. So I've access the manual bolt that manipulates the sunroof. It's a T-25 torx.

I moved it back and forth but I can't close it (even when pushing up on the opposite corner). I can open it a bit more to see what is (and isn't) happening inside. Here are pics with the flashlight in various positions:

 

I was able to close it back close to where it was before (when the shop returned it to me after a quote):




Also, closing it doesn't really help me much as I need to "get in there" and see what's broken or misaligned and fix it. That's where I am now in this process.

Any tips on getting whatever I need out of the way so I can repair this? I don't need to drive it (it's a project car) and it's in the garage out of the elements.

 

I know all about mine but I have the panoramic sunroof so it goes in a completely different direction than a standard. I did notice that your parts list shows only 2 long guide rails and they're relatively inexpensive. You're going to have to take a really good look in there and see if your two plastic guide rails are actually broken or if they just came out of their tracks. From the pictures you just sent, they look decent. They're the long black plastic rails that bolt to your glass. They slide in metal tracks that are bolted to your roof. You might be able to pry them back in.

 

You know something weird? I can't find a single repair video for standard sunroof track repair for a W221. I see motors and I see entire sunroof removal and I see everything possible for the panoramic type. This would be a good opportunity to create a how-to video. If you can't find a way to repair it in place, you can drop the headliner, drop or lower the roof tracks, unscrew the guides from the glass, slide the guides out of the tracks, clean the tracks, lube the tracks, slide the new guides in, screw the guides into the glass, bolt the tracks back in, adjust everything so that it closes squarely, put the headliner back. My biggest fear would be getting a greasy fingerprint on the headliner.

Whatever you do, clean the heck out of those tracks and guides and lube it up with the Mercedes sunroof grease. Lack of proper lube is the cause of most sunroof failures.

 

See attachments.Afterward to lubricate sunroof WIS doc shows 0019898451 (shop size), you can use: https://www.ecstuning.com/b-genuine-.../0019894651~a/ , Plastlube, or some members have used white lithium grease. I suggest MB.

 

When I called the MB parts department and explained my issue ("I heard a crack and the sunroof seemed to be off track now...), over the phone, the guy thought I needed these:
221-782-01-31-64 "Guide" $66
221-782-02-31 "Guide" $62




I was like, hell, that's waaay less than the independent was gonna charge me ($1,600 parts and $1,500 labor). So, yeah, I ordered them hoping that'd be my issue.

When I got them I noticed that the tip seemed to look just like the broken pieces that I fished out a few days ago:



So, this is very promising!

Yeah, I noticed that, too. No standard sunroof videos. I won't promise a how-to video, but I'll try to remember to take pics.

I'm suiting up and goin' in...

I picked this up today, too!



A-001-989-46-51

Over $100USD 😬

 

THANK YOU SO MUCH, @konigstiger!

How can I find these diagrams myself? I'm happy to pay a subscription. I recall being able to buy access to these directly from VW/Audi when I had VWs and Audis. Basically I paid like $25 for 24 hours of access to their "Erwin" system and simply downloaded every PDF for my vehicle at the time. Money well-spent.

 

MBUSA offers online parts catalog @ $92 annually, and 24 hour work instruction sheets (WIS) inclusive of STAR wiring diagrams @ $75. Alternative is to search ebay: “wis epc Mercedes” for copy make sure your model year & model year is included on disk.

 

Awesome Thanks!

What are "24 hour work instruction sheets"? Not sure what that phrase means.

Also, I just confirmed that it is indeed the same part that I fished out:

 

I used white lithium grease on my sunroof at first because I didn't know any better. It did free up the movement of the sunroof nicely but it also collected dust and dirt. I didn't realize it then but the track area is exposed to outside air when I'm driving. You might get better results with it if you don't live in a big dust bowl like I do. ECS is where I got my Mercedes lube. It's actually quite a bit. I've lubed it up twice now and I still have over half left. It doesn't collect dust and dirt as easily. I've heard that there's a Honda sunroof lubricant that is similar.

Here's how I clean mine... Open the sunroof all the way. Clean out the tracks and guides with alcohol soaked q-tips until they come out clean. Open and close the sunroof a couple of times and do the q-tip trick again. Put some alcohol on a rag and wipe off any rubber seals, wind blocks and weatherstripping. Dip a q-tip into your Mercedes lube and wipe it onto your tracks and guides. Use a new q-tip every time to apply more. Wipe some lube onto a finger or two and wipe it across all the rubber and plastic parts. Wipe any excess off and you're done. I did it initially about 2 years ago, then again a year later. It was still pretty clean. The MB lube is good stuff! The cables run through a liner so don't apply any wet lubricants to those. I used dry PTFE on mine when I rebuilt the motors but that may not have been necessary.

 

You can put the rest into 1/2 ounce containers and sell it to forum members for $10 a pop. LOL

 

The docs I posted are available for 24 hours.

 

Ah! So it sounds like the VW/Audi system!

https://erwin.audi.com/
https://erwin.vw.com

 

I took apart the interior according to the instructions above, then got stuck actually pulling the headliner down (more on that later).

As I was looking around, I saw that there was a rubber cover over the broken rail that I intend to replace. I noticed from the outside that I could dislodge it, so I did and, boom! I can access the 3 screws that attach the glass to the broken rail.

Seen from the inside of the car (the 3rd is a little to the right of this image):


Once I removed those three T25 screws and one plastic pin (pinch it from the outside), I was able to wiggle free the offending rail:



I noticed that the female rail is also cracked. I'll have to order that, too:


After removing all of that, I was able to use the manual sunroof bolt to finally do the back and forth dance to get it to retreat:



Annnd here's where I'm stuck.

I cannot get the headliner to easily release from this area where it reaches from underneath and grabs hold of the open area. This 1.5-2cm lip is holding the headliner in place. I don't want to tear it off and deform it. Not sure how to proceed.




The instructions read, "Loosen roof paneling (1) from sliding roof frame." Not really sure how to go about doing this.

 

I don't know if yours is held on with a fastener but mine just pulls down. Once the visors and overhead console and grab handles are unscrewed, it just pulls.

 

Does your car have this 1.5cm plastic lip? If so, did the lip stay in the sunroof area or did it come down with the liner?

 

No. My headliner rolls upward and butts up against the sunroof. No trim. I can pull it a little and see inside without unscrewing anything.

 

Maybe it's for the Alcantara?

I just checked and I'm able to get a trim tool between the plastic lip and the headliner. So, it seems that the lip is there to hold the Alcantara. Maybe I have to dislodge it with the trim tool...or maybe the plastic lip is designed to come off first. I'm tired. I'll try again tomorrow.


Fun fact: Alcantara is not a natural material (I always thought it was). It's a synthetic material made of polyester and polyurethane. And "Alcantara" is the brand name of the creation.