How can I remove the sun roof to fix it. The mechanism that makes the rear pop open has failed on one side so the sun roof is lopsided and does not close properly. Any tips or advice will appreciated.

 

You might have to pull the entire assembly. That is a major PITA.
But first pull the glass and inspect things in there.

 

The very mechanism is somehow jammed. It will go back maybe 6 inches and that's it! How can I get the glass off?

 

If you can get it to tilt up there is plastic covers on each side. I think they slide forward. But if you look with a flashlight you should be able to see which way to slide it.

Then you will see the 3 screws on each side to remove the glass. Then you can check some more.

 

It will slide open maybe 6 inches. Tilting IS TOTALLY OUT OF THE QUESTION.

 

Then it is going to be a major pain.
See if you can work those covers off then you can unscrew the glass.

 

I tore the first one up to get it off, not knowing how it was anchored. Volvo uses what I would call rods (or short pieces of plastic rods) that slide into partially open clips. Those covers slide toward the rear, but can be really sticky. The last one I did, I drilled a 3/16" hole about in the middle I think, stuck the tip of a needle nose pliers in the hole, and tapped the pliers with a hammer near the tip where they went into the hole in the cover. Even this took some significant effort before the cover slipped back and released. The one on the other side offered almost no resistance. Once the covers are off, you can see the mechanism. Hope this helps.

BTW: those links dry out and get dirty with road crud. You'll probably want to clean them up including the track they run in, and lightly grease or oil the "cam" link which has metal sliding on metal to lift and position the glass. If its dry it could break like one of mine did.

While you're in there, inspect the seal flange that is laminated to the glass. Over time, water seeps between the glass and the seal and can deteriorate the glue that holds the flange to the glass. When that happens you have a "mysterious" leak, because you can't see why the water getting past the seal isn't dropping into the tray and draining through the hoses. A junkyard glass is probably your best solution if that happens. Of course, once you take the glass out of the junker, it's really a junker after the next rain storm. We drift.
JB