Polar Bear

I have a W221 with a Panoramic roof. Last night we got some really hard (not violent) storms, and my car was out side. I we to drive my car, and the sunroof would not open. I could hear a relay clicking and the see the lights dimming, but the roof would not budge. Car has around 30k on it, and has all schedule maintenance. A few observation.

Initially - the mesh cover would try to close beyond the limits and causing a gear grinding sound. It would stop of I left off the switch (which of course I didn't hold long. When retracted, the shade retracted longer than normal, and caused a distinctive "click" sound like it had reached a part underneath the upper console between the two front and rear sears. The rear shade works fine. When connected to STAR, the glass works, and the shade works independently, however I cannot normalize either of them. Doing an initial startup from a new unit, it attempts to move the shade and the glass stays back, stationary. When the mesh closes, I hear the gears grinding for about 10 seconds. I know this is not good to hear this, but there is no apparent way to cancel the process - in DAS, via the switch, ignition, etc. Anyway, it has not normalized. I have used the emergency provision to close the roof and the roof is not out of alightnment, so it seems there is a torque stop type switch or contact switch malfunctioning. It has the alcantera headliner. It seems this is a fairly common issue with these, and it look alike I may need to remove the A pillars and the B pillars to get to the motor which seems to be above the driver sun visor for the glass and the passenger side for the mesh.

Has anyone tacked this? Doesn't seem to be too difficult. Any help would certainly be appreciated!

Polar Bear

Rather simple issue that has now been resolved.

DubVBenz

It's always helpful to share the details on posts like these.. whether it's about cars or anything else.

BenBoosted

What was the issue and how did you resolve it?

DJSteve

I think I've developed the same issue! Please, what was the simple solution?

Thanks in advance!

Polar Bear

To respond to the several questions requesting the resolution that I should have thought to have included earlier, it was one of the two motors that are above the sunvisors. On the driver side, there is a cable driven motor (that is shared with the W211) to move the glass. On the passenger side above the sunvisor, there is another identical motor that controls the sunshade. It has a Hall effect sensor to inform the system of its location, and over time and usage, the design of these motors have a flaw where the casing stretches. When the shade or the roof reaches the stopping points, it adds torque to the motor, which in turn cause the motor housing to stretch in opposite directions. When this happens, the work gear slips that operates the shade. There are several solutions - replace the motor and install it; compress the housing back to it's original shape before it stretched to when it is under torque and allows slippage, or open up the motor and apply some o-rings around the gear which will prevent the assembly from moving under torque, which is the simplest and least expensive option. When complete, reassemble and normalize with SDS. The shade and glass roof will begin functioning normal again.

Zerocarpileup

Zerocarpileup

Jason B

Suede headliner?