E350 Estate 2011. W212. Sunroof very slow to close/will not close

[Seftonbarn]

I have had my E350 estate for a few months now and the sunroof has always been a little slow on closing. Today it was particularly slow. Occasionally it would stop and then open a little before stopping (as if the motor is sensing some sort of restriction). From outside the car I selected the switch to close and used my hands to assist the roof to close and it did close effectively. I don't really want to open it to investigate until I have some ideas as to what to be looking for. A lack of lubrication is a doubt in my mind because it opens so smoothly. Any help appreciated.

 

[Teego]

99% it's a lube problem and a cheap and easy fix.
I had similar problem on my CLS.
Click the switch and it opened automatically all the way.
But to close I had to hold the switch. If I released it the roof would stop.
If you think about it, the safety switch only has to work when the lid is closing.
So, open the roof and clean out the runners and quides. Get a vacuum nozzle in there if you can.
Make sure it's properly clean - use the white rag test.
Then lube the runners and guides - BUT NOT TOO MUCH or it will attract grit.
I used Scottoil chain oil I had lying around. I'm sure any lightish oil would do.
Spread lightly with a paintbrush.
Open and close the lid a few times even if you need to hold the switch. This will spread the lube to where it needs to be and Bob's your uncle.
Did mine about 3 months ago and it's perfect.

 

[Seftonbarn]

Thanks Teego. That all makes sense. I had some roof bars fitted once that were slightly mis-aligned and fouled on the path of the sunroof. On that occasion it failed to open and backed off (pressure sensors I guess). But your recommendation sounds good. I will give it a go and report back my findings.

 

[Seftonbarn]

Correct Teego. Many thanks. I couldn't really do a lot of cleaning as access was very poor. I sprayed a little 3 in one on the internal rails and guides. This improved it slightly but it still wouldn't close on its own. To the rear of the sliding glass are rails that are mounted externally on the roof. They are protected by a rubber seal. As the roof opens a guide at the rear of the glass roof pushes through the opening in the rubber seal; a bit like a plough. I used a spray tin of silicone with a small nozzled pipe and sprayed this rubber seal. This greatly improved the problem so that the roof was able to close on its own. I then opened the roof and then, with my silicone spray at the ready, I selected the switch to close and followed the plough effect thing spraying silicone spray to the inner parts of the rubber seal. It is now perfect. Thanks again.

 

[jonboyE63]

I cleaned & lubricated my panaramic sunroof this morning as it was exceptionaly slow when closing - i treated the rubber seals with Muc-off chain lube & it's working perfectly again - the tip about lubing the guide through the rear rubber seals was fantastic - thanks

 

[milleplod]

I use this - TASC SP1 Sunroof Soft top Lubrication Grease Webasto Britax Golde Inalfa NEW | eBay

You can also get Mercedes-branded stuff.

Pete

 

[MikeInWimbledon]

Another top tip is to just make sure you use the ruddy thing a few times each year.

It's nothing specific to MB or the W212 - people pay a fortune for these roofs, but often don't open them for years on end. Then someone opens it and find that there's an issue - often attempting some heavy handed "repair."

So when stuck in traffic and "a bit bored," it's always a good idea to open the roof, all four windows, and to fiddle with electric seats.

As they say, "use it or lose it."

 

[MrDods]

My c63 failed was going to cost a fortune luckily was under warranty

 

[Petrol Pete]

Agree with the comments on cycling the sunroof now and again , I cleaned and lubricated mine a while back . It is on the MB sunroof safety recall list, so who knows I might be getting a new one soon . On a 15 year old car !

Hope not , I don't really want MB messing with it. My guess is if it hasn't fallen out in the last almost 150K miles it ain't going no where any time soon.

 

[jonboyE63]

My c63 failed was going to cost a fortune luckily was under warranty

Mine failed & was rebuilt under warranty within the first year of owning the car so I was fairly sure it just needed a good lube...
Is it just the early models with sunroof recalls..??

 

[Petrol Pete]

The recall covers more than three quarters of a MILLION Mercedes Benz cars. If yours was on the list you should have got the letter by now.

 

[jonboyE63]

The recall covers more than three quarters of a MILLION Mercedes Benz cars. If yours was on the list you should have got the letter by now.

wow...thanks - no letter so I assume mine is ok..

 

[Catweasle]

I have a different problem. When I press the sunroof button there is a whirring sound as the motor operates however there is no movement, I assume that there is a broken cog in there so can anyone help me with a fix please?

 

[Catweasle]

It was the cog!

 

[MikeInWimbledon]

Yep, could be right.

I'm no expert but I think it might be difficult to rotate that.