95 e320 Wagon Sunroof: It must be possessed ....
 

The wagon’s sunroof must be possessed ..... some days the switch will make the roof tilt, slide and do all the things it is supposed to ..... other days, like today, it now wants to stay in the tilted position, open.

The last time this happened I used the driver's door lock roll-up feature to close it, so I am "guessing" it is the switch in the overhead, but I don't know.

I did several searches and one indicated a control module under the passenger seat, but that was for a sedan. The other was for a wagon, but talked about an antenna ground in the right rear .... so I am really confused.

Any help or suggestions (with rain approaching) would be greatly appreciated.

Haasman

sticky sunroof
 

This happenned to my 1994 C180 last year and I did 2 things. First, I bought a brand new high powered battery then I went to the dealer who splattered a good deal of the Benz grease on the rails and hinges(whatever they are) and its working like new since then.

Thanks for your reply. I feel it could be the switch. I think I should pull it down from the overhead location and check the contacts.

Haasman

Today I used the tilt feature, which it did, and then it wouldn't come down. Wouldn't do anything. I had to close it with the manual closing feature in the left wheel well.

Any sun roof pro's with suggestions? Please!

Haasman

Haasman:

Do you have the "convienence package" that allows you to close the windows, etc from the door locks?

If so, could very well be the relay box, under the rear seat, I think.

This little "feature" is why I would never get a car so equiped -- if there is something wrong, the only repair is replacement of the entire box (yes, all the windows and the sunroof are relayed through the box) -- and is is EXPENSIVE.

I'd certainly check the switch, it's vastly cheaper than the relay box. If it always closes with the door key, then it's very likely to be a bad switch.

Get some lube from Rusty, too, he sells it in a nice 2 oz box for $5 or something like that, a lube cannot hurt.

Peter

Peter

Yes it does have the "convienence package" ... but in a wagon, where would this be located?

Now that I have closed the roof and the overhead switch doesn't do anything .... a couple of questions:

-How does one gain access to the overhead switch?

-I checked the fuses, but I certainly do it again. Should I use the manual feature to roll the roof open to lube the tracks?

-Finally, if it isn't the switch .... where would you look next.

Thanks for the help,

Haasman

Don't know where the convenience "relay" is, probably the same place as the sedan (under the rear seat), but lacking a manual, who knows?

Is the switch in the housing where the overhead light is like it is on the W124? If so, just pull it (as if changing a lamp) and you should be able to figure it out.

If it's not the switch or fuse, hope it's the motor, not the relay. No replaceable parts in the "relay", just the whole box.

Peter

Thanks Peter

To pull the overhead switch, what does one have to do?

Haasman

Don't know -- too new for me! I'm still in the W124 chassis. In that one, the switch is in the overhead lamp holder, it pushes over and pulls down for a bulb change, and the sunroof switch is right next to the lamp holder. Never taken one out, though.

Peter

I pulled the switch and it seems fine. I then worked the switch while carefully listening to the sunroof motor. I can hear it clicking but no sunroof panel movement.

I used the manual feature and made the panel go through a full range of movement and tried it again. Nothing.

Do you know should the manual movement be easy. I noticed that in using a socket and rachet is took a bit of effort to make the panel move.

So any suggestions as what to do next?

Since the motor makes a noise via the switch but doesn't move it, I am wondering if I should roll it back, lube everything I can including the cable (something I have not idea how to do) and try it again. Maybe everything is just in need of a lube?

Haasman

Definitely lube the sunroof rails. Cable will be more of a problem, I'd avoid that unless forced to.

Manual operation is pretty stiff.

Closed location is by microswitch, so it's possible that something has gotten out of alighment in the motor itself, too. Does it just click or does it hum? If it hums or buzzes with the roof somewhere besides closed and flush, its dragging too much and the motor is slipping on the clutch. If it just clicks, something is wrong with the microswitch control inside the motor, most likely.

Peter

Peter,

As always, thank you for sharing your experience and wisdom.

It seems to make a click. Sorry I am listening up front and the motor of course is in the back.

I will check and try to lube the tracks.

I will try and lube the rails. Any close substitute to the infamous MBZ lube? Any mixtures of products to approximate the lube such as Siliglyde and say silicone spray?

Haasman

My experience with my '95 E 320T's sunroof might interest you:

Since new, the sunroof has always been a pain and has never work correctly.

On my first complaint, the dealer changed the motor (under warranty), it worked fine for a week and then quit again.

Then they changed a relay which is located close to the sunroof motor on the left rear panel (just in front of the spare tire).

This cured most of the problems for a while, the dealer commented about this relay being a common culprit on sunroof problems, especially for the wagon (the relay is not cheap though, I believe).

Full lubrication is a must, on my car is done every oil change.

Still, today the sunroof sometimes refuses to tilt open unless you help it a little with your hand.

Thanks .... this is beginning to sound familiar ..... I am wondering if the relay is bad. I hate to ask how much .....

I just looked it up. Fastlane lists it as:

P2065-73947 Sunroof Relay

List: $66.00
Price: $82.50

It is more expensive than list!

I am quite sure the tracks need to be lubed.

Haasman

FWIW, my sunroof started working intermittently, and then one day it got stuck halfway open and wouldn't close.

I took it to a local MB independent, he noticed the tracks were dry, lubed them up, and then it moved just fine.

I make a point to lube it every oil change, and it has never acted up since.

suginami

Are you using the MBZ lube specific to the sunroof?

Haasman

Where does one lube a sunroof for the tilt related mechanicals?

Yes. Mercedes only sells it in large quantities. My local MBZ independent provides it to me for free.

Rusty Cullens at *************** sells a nice 2oz can of sunroof paste for about $5. Beats $50 for a quart tin....

Sticky lift is still a function of lack of lubrication -- the side rails (lift angles) slide forward past the closes position and cause the sides to hinge, lifting the rear of the panel. If the slides are dry, it won't slide forward very well, and the panel won't lift properly.

Peter

Thanks Peter,

This is what I am targeting to repair. I am guessing the who setup needs to be lubed.

Can the rails etc be lubed without pulling the panel?

Haasman

Open sunroof and apply paste to slides and pads. If you cannot get the sunroof open, you will probably have to detach the headliner and push it back to get some lube in the appropriate spots.

Peter

The Exorcism Is In Process ....
 

I finally got the roof to move .... Yeah! I worked it back and forth using the manual crank setup in the left rear. I put some MBZ sunroof lube on the track.

It will now move under its own power, that's the good news ... but it is still slow. I figure I need to get to the gears and lube those and possibly the cable. So three questions:

1. How does one get the motor/gear assembly out? I see the two 10mm bolts, I took those out, but it still is held in there. What am I missing?

2. Can the gears be lubed without taking the entire assembly off/out?

3. If the cable needs to be lubed, what's the best way to do that?

As always, thanks in advance,

Haasman

Ah .... partial demonics are still there ..... after writing the above, I worked the panel some more and found that at about 3/4 of the way open the switch seemed to make it want to reserve direction.

Geesh! What is going on?

You must remove the headliner to get the motor out, I think, and the cable tube has to come out. May be wrong. Motor may slip off the cable tube once you have the cable out.

At least you will have to pull the cable to get the motor off, anyway -- remove from the bridge and run "closed" until it stops moving and will pull out. Do not use the sunroof paste on the "brush" on the end, there is a grease for that.

Chances are you either haven't gotten the slides clean enough or the motor is slipping, the latter is more likely if the manual operation is easy and smooth. I believe the clutch can be adjusted, but don't know the instructions for that model.

Peter

Update

(Thanks for all the help on this BTW)

The panel is moving back and forth. I removed the inside panel and figured out how to remove it. The underside of the sunroof mechanicals now exposed.

I lubed everything and it seems to operate well going forwards and back with three observations:

1. It does sound like it is scratchy sliding forwards and back. Does indicate dirty rails? If so how would one go about cleaning them?

2. The overhead switch doesn't work exactly how one would expect: Sometimes when the roof is open, by pushing the switch up the roof will close but not by pushing the switch forward. Is this a setting/adjustment?

The motor is heard whirring when the above occurs but the panel doesn't move. Does this mean the clutch needs to be adjusted?

3. On the driver's side, when after the roof is tilted and it is brought down it slams. I peeked up underneath and noticed one of the tilt pieces is broken. Can these individual pieces be replace? Easily.

Thanks again for all the help on this .... hopefully it will help others.

Haasman

Any sunroof ideas?

Get new lift angles -- about $100 each. Do both, if one broke the other is bent and will break soon.

Remove top panel -- held on by four bolts on the side, I think, after running the roof all the way back and removing the chrome rails.

run the frame back up, then unscrew the translation bridge from the lift angles. The entire lift angle assembly will rotate out of the frame if you lift up on it, then rotate the top edge outwards. Kinda fiddly, I had trouble and my brother just grabbed it and pulled it out....

New ones need to be lubed and installed. Make sure the side are even on the translation bridge and that the bridge is straight. Make sure the cable is straight and the retainer clamp isn't twisted or bent.

To install the roof panel, you will have to insert some 8mm allen wreches through the alignment holes in the fittings and into the new lift angles while tightening the bolts. YOu will probably have to pull the bridge back a small amount and push the panel forwards to get it to fit correctly -- it must push agains the front seal firmly so that the rear won't bind on the close at tilt operation.

Open the sunroof, install the chrome rails, and adjust for height closed by loosening the crosshead screws on the rails and turning the slotted screw on each side up or down to get the front level and within 1 mm of the roof level -- below, not above.

Once you get the front set, put the 8mm location pins back in, loosen the panel attachment screws, and adjust the rear edge to be slightly above the roof, within 1mm.

Deviations from the height specs can cause wind noise.

Peter

Thank you for the detailed response Peter. I will replace the broken pieces.

Any ideas as to why the overhead control switch is so weird?

"The overhead switch doesn't work exactly how one would expect: Sometimes when the roof is open, by pushing the switch up the roof will close but not by pushing the switch forward. Is this a setting/adjustment?

The motor is heard whirring when the above occurs but the panel doesn't move. Does this mean the clutch needs to be adjusted?"

Haasman

No, the broken lift angle causes severe drag. The closed position is set by microswitches in the motor assembly. Full open and full tilt are set by the slip clutch (that is, the motor will turn but the clutch will slip).

The broken lift angle will cause very hard operation, so the clutch slips. When selecting 'up', the motor will run as long as the switch is pushed, if pushed forward for 'closed', the bridge will move some and the motor will stop on the microswitch, but the pane will not be completely closed since it's only partly connected to the bridge.

Eventually the broken lift angle will cause the bridge to cock and jam, so don't use the sunroof until you can get it fixed properly!

Peter