PeachParts Mercedes-Benz Forum - View Single Post

bhatt · #3 08-30-2011, 10:08 PM

OK did some more diagnosis and here's what I have found.

When I push to the open, close, or lower positions, the motor goes "click-click". It tries to move (first click) then shuts off immediately (second click). It is obviously protecting the motor because the roof won't move.

When I push to the upper position (raise the back of the roof) it doesn't do a thing. No noise at all.

But here's the weird part. I put a 4mm hex socket into the hole in the motor (under the left light cover) and as hard as I crank it with a huge socket wrench, it won't turn in either direction. Tried to hit the switch and lean hard on the wrench in the same direction, but I can't turn it.

I pulled down the accordian shaped rubber on each side (interior of the car) of the sunroof. Sprayed the mechanism with about a 10 second spray of WD40 on each side. Roof still didn't move.

So now I'm not sure if it is the mechanism, or maybe the motor.. that's my new suspicion now!

Is it possible that maybe the motor was getting slower all along (not a problem with the tracks)? And now it is jammed up/siezed?

The weird thing is last summer when it started to get slow I in fact DID lube the roof but it didn't make a difference. I lubed every sliding chrome rail I could find but it didn't make a difference at all. I used the MB lube that I purchased a few years ago (had some left) so I used the right stuff. Didn't speed up the roof a bit.. it was as if I didn't lube the roof at all!

So I'm starting to think that the best idea is to pull the motor and see if it turns. If it is jammed, I'll replace the motor. If it turns without the sunroof attached, I'll keep looking into the mechanism.

Any further thoughts before I start tearing this apart?