W124 Sunroof Stuck in the not-quite closed position

[Madanglian]

Hi everybody here is (yet another) sunroof prob.
I have a 1992 200TE estate with a sunroof which is about 10mm below the fully closed position and won't move either way.
I have opened up the back by the spare wheel and I see that the motor works and rotates in both directions but nothing moves. Having undone the motor assembly fixing screws and turned the motor round, it seems to me that the inner cable has completely disappeared.
Under normal operation does the cable rotate or (as I suspect) is it a pull-push affair? What is the curious plastic cam/microswitch assembly for?
Is there another relay/solenoid that I can check to make sure the electrics are ok? I am puzzled that the lift/lower switch makes the motor turn clockwise whichever way you switch it.......
Thanks for any help
Madanglian

 

[Jim Gallagher]

I had an experience with my '94 E220. The sunroof stopped sliding closed with about 150mm to the closed position. With the switch being pushed , I placed gentle forward pressure with my hand on the roof and it closed successfully. I applied some grease to the runners and the problem has not recurred.

cheers

 

[Madanglian]

OK Guys (and girls) here's the gen

Well it's fixed (at least after a fashion)....... :?
Since there seems to be so many probs with sunroofs I thought I would add the benefit of my experience for any poor soul who ends up in the same situation.

The sunroof cable had indeed disappeared, having been forced up into the space between the roof & liner. It got buckled by this and the whole mechanism seems to me to be a very poor design and makes me wonder how anybody's sunroof closes without buckling the cable.... :roll:

I undid the outer cable from the motor (very fiddly and messy) by undoing the clutch nut (the one under the plastic "manual adjust" nut) and taking the cover plate off the other side of the gearbox. The whole gear wheel assembly then comes out (covered in grease) and after removing some kind of guard plate, it was possible to remove the end of the cable from the motor/gearbox assembly. Thankfully the end of the inner cable was visible and just pulled through. After putting the whole lot together again the motor was able to pull the sunroof open .

But of course the inner cable was so buckled it wouldn't close the roof again. With lots of pulling and pushing I could get it back to the not-quite closed position again, and no further. No better off there then. :x

Looking at this very forum, I found that it's possible to take off the trim panel on the sunroof of the 190, so I thought well maybe .... and yes! :idea: you can get access to the mechanism by removing the four popper studs and sliding out the trim panel.

It was then that I discovered why my sunroof had been nearly closed: some kind former owner (or service technician) had rammed in a couple of pieces of soundproofing material to jack up the roof :!: Shortly afterwards I also discovered that all the opening and closing I'd just been doing had left a couple of scratches in the paintwork

OK, important bit. You can only manually close (or lift) the sunroof by pushing forward the black steel crossmember which the cable is actually attached to, and which you can't get at unless you take off the sliding trim panel.

In the end, I got my sunroof to close by pushing the crossmember so far forward the back end tilted, then pulling it backwards using the motor till it got to (what I thought was) the normal "closed" position. This was quite easy with the trim panel off, but who wants to go around with no trim panel on the inside of the sunroof? (We are talking Merc here) How to get the trim panel back on? Open the sunroof again........ :roll:

Closing the sunroof with the trim panel on was a bit of a palaver but I did achieve it in the end by looping a couple of pieces of string around the crossmember then feeding the ends through the gap between the two pieces of trim panel whilst putting it back in. It was then possible to close the sunroof properly by pulling the ends of the string forwards. As the string was only looped around (not tied to) the crossmember it was quite easy to take out.

Well done to anybody who has managed to follow all this. You must be desperate.

I have now closed my sunroof and disconnected the electrics on the motor......... :!: