C300 2015 panoramic soonroof problem
 

Hi. I have c300 amg package 2015 (not amg motor) with 22k miles, in great kept condition. Recently the temperature has dropped and it is 13 degrees. As i was going in the highway i opened the roof and it worked, which later on I closed it as I was driving. Fast forward later on the day, I try to open the roof. The shade opens, the right side of the roof lifts up butt the left side does not move as if its stuck, or the motor does not even lift the left side. As i proceed to open it , the roof does not open and stays in place because the left side of the roof does not move at all but the right side does but thats as much as it goes. from the outside it looks like it is tinted on one side and the other is stuck in place. I wonder what might be the problem? Is it stuck, it it bcs of ice maybe, fuse problem, maybe something stuck on the left rear side of the moonroof?? Any way to push it open without breaking?? I will try to get pictures. Please help

First thing I would do is warm it up (why were you monkeying with it anyway at 13 degrees?). If you have a garage, park it inside with a space heater or something to rule out ice. Either way, I wouldn't be applying pressure to anything at those temps... everything is going to be more brittle.

Once you have done that, check both sides to see if you can see the tracks and make sure nothing popped out. Pics would help.

thanks for replying. I opened the sunroof as i was on the highway for some air. I will deffinetely get some pics. It seems like the right side is fine and ready to open but something is preventing the left side from moving. Is there a way i can manually lift it up to see the tracks ??? Or even lube it up ??

i dont have a garage and temp here now here is at about 20 degrees which will get warmer. I have no gotten a better look for it myself, the motor seems fine but what happens is that as the right side raises, i proceed to continuously press the button to open it then bamm it just lowers as if it knows there is a problem.. or maybe a sensor.. its just wierd. I know for a fact that the left rear side is not moving as it is stuck. I will take some pics and vid tomorrow. My next step is to check the fuse.. then remove the panel near the front mirror to see if i can manually open with the allen key. Its just annoying because the car is in great shape and sucks to bring it to the shop. I will definitely never open it in the winter or whenever there are strong winds.

Broken guide rail. Have to replace both sides, as the other one will break shortly after if you don't. Bulletin calls for replacing the guide tubes between the rails and motors but I think that's overkill.

Parts are over $2k and assume about 8 hours of labor. Headliner comes down and it has to be run in with SDS so not really a DIY repair although you could if you took it to get programmed after.

Is this a known issue on the panos? All of them? Assuming if there is a bulletin it's a somewhat common issue?

In any event, I looked at mine and all that's in that corner is a bracket connected to a plastic wheel in the guide rail. As long as you wait until it warms up, I don't think gentle pressure will hurt anything.

i didn't buy warranty from the dealership. I dont think the car has warranty since its been more than 3 years of car production. Thats upsetting. I hope nothing is broken and its a quick fix.

I have uploaded pics

Don't see any

https://cimg7.ibsrv.net/gimg/www.mbw...67aa760e70.jpg
https://cimg8.ibsrv.net/gimg/www.mbw...7316a2ff9c.jpg
https://cimg9.ibsrv.net/gimg/www.mbw...1eece53847.jpg
https://cimg0.ibsrv.net/gimg/www.mbw...1b5b7a36d4.jpg

Looks like the guide wheel is just hung up on something. Have you tried giving it a little help? I wouldn't use Hulk strength -- just a little Dr. Banner push should determine if it's just hung up on something or if it's a guide rail issue.

https://youtu.be/SA0JfPlgTnE video of the roof opening

i tried but no luck. It cant be possibly be frozen.. did u see the video

It's broken, thats why only one side is lifting. You don't have to like it, but we replaced them all the time at the dealership. Very common failure, cheap plastic parts in the rail assembly that get brittle and snap off. Hope all you want, then when you actually want to fix it, prepare for a big bill.

Yes, it's the same roof system on the 117/156, 205/253, 217/222 and now the 213. The parts are cheap and they fail, the bulletin just says to replace everything to avoid premature repeat failures.

It's not the rear corner that breaks. It's the part connecting it to the front. There is only one cable that moves down each side, it relies on a lever/cam system to lift the rear first as to moves, then start sliding the roof rearward after it lifts. If it's broken it can't lift so it can't slide. There is only one motor that drives the whole unit so it can't go past the lifting stage on the working side either.

It will take a great deal of force to push it open manually while turning the motor by hand, and even if you do, you only get the rear up, you still can't power it open/closed as the drive on that side is broken.

do you suggest i manually open it with the allen key to see it the left side lifts up??

Can someone at least offer at least something i can do to check myself if indeed there is 0% chance of me fixing it myself. I plan to open the top console and manually try to open it.

It sounds like it's time to bring it to the dealer. Last thing you want is to do more damage and then the roof is stuck open.

The motors are working fine. Its just one side that seems to be stuck. I need to find a trustworthy dealer

None of my business by why obsess over this in January? Close it up and forget about it until spring. Otherwise you run the risk of getting it stuck in the open position and you'll be forced to take it to the dealer and pay for the full repair.

The allen key goes into the center of the driven gear in the motor assembly. It won't tell you anything you don't already know. It will only help if your motor was bad, which it isn't since the non broken rail is still moving.

Is there a way to just replace the rail which might be broken and not replace everything. Thanks for your help.

you definitely have a point there, i just got the car in September and it's really upsetting me now.