Sliding roof ... repaired!

[AlanMcR]

History:
A few months back the sunroof on our 98 E300DT began to jam. It would tilt up/down and close properly. However it would only slide 1/2 way back before stopping and making ominous mechanical clanking. I managed to fix this.

MB fixed this problem later in the W210 lifecycle, and there is a replacement part: the entire sliding roof. Since it seems to be a common problem, I thought I would post a fix. If you are mechanically handy there is a permanent repair. Read on...

What is really wrong with it:
The panel is operated by twin coiled spring mechanisms which resemble 1/4" ropes. These springs are used to push and pull the sliding panel. To open the panel, the mechanism is *pushed* by the rope spring. Pushing on a rope is a bit difficult. To allow this to work, the spring rope is constrained within a very narrow plastic channel.

One portion of this channel is made by a 2"x1/2" plastic panel. The panel is only held in by a single screw on one end. After much use the panel comes loose and allows the rope spring to pop out of the channel. Then the roof stops and the rope snaps around uselessly. If you keep going it is likely kink and be ruined.

The fix:
Basically you will need to drill a hole for a screw that will fix the other end of the plastic panel.

To get to the panel you will have to remove the rubber bellows on both sides. First tilt up the glass. They are clipped in rather lightly. Just pull them towards the middle of the opening and they will pop out.

The panels are about 3/4 of the way back along each side. You may need to remove the moonroof itself (6x torx screws) to get a good shot at the panel. Do not try to move the motors w/o the moonroof screwed in place. Parts will break.

Before drilling and driving the screw, make sure that the panel is fully pressed into place. Otherwise you are just cementing the current problem into place. The new screw should be positioned symmetrically with the old one, just on the other end of the panel.

Good luck.