Cabriolet top won't close without manipulation

[Alfieboy]

I have a 2003 C4 996 Cabriolet.

I have been having trouble with my cab top in the past month or so. The cab top retracts just fine, but takes several tried (often hours apart) to get it to go back into the closed position.

I followed the incredibly helpful DIY walk-through on how to top-up the cab motor's hydraulic fuel (took about 30 mins, I'm very careful and a novice), but that didn't fix the issue - it was a tad above minimum before I filled it. Further self-checking has identified the issue. There are 2 motorized 'flaps' with same material as the cab top on one side of them (i'll call them flaps for now, in lieu of learing their official name), one either side that that go into a vertical postiion with the cabriolet top housing when the cab top is closed and come up from the housing, rotate and become horizontal to close up the gap between the interior and exterior of the car when the cabriolet top is open/retracted.

The problem comes when I got to close the cabriolet top, the driver side 'flap' does not fully rotate back from it's retracted horizontal position to being in a vertical position so that it can assume it's stored position in the cabriolet housing when closed (cab top up). By gently manipulating this 'flap' back into the same position as on the passenger side, the cab top motor engages and the full close mechamism works perfectly (note the owners manual says do not attempt such things, as it's dangerous to stick your fingers in the working mechanism, but as this was on the peripherary, I took the personal choice to do so. You should consider your own risks when doing such a thing, as the cab top sprung into action as soon as the flap was in its correct position). I had my wife in the car operating the close switch, so I was able to do this.

So, here's my questions:

1. What is the flap called?

2. It looks like the rubber elements of this flap are in poor condition, and that they are obstructing the ability to rotate into their desired position and thus stopping the mechamism. How big a headache are they to fix/replace and is a DIY or dealership task?

P.S. Loren/Others If you want me to update the DIY Cab Top Hydraulic Fluid Replacement/Top-up with some comments for the novice, I would be more than happy to do so - as there's a few blanks that need to be filled in.

[Alfieboy]

Still doing it, it's quite funny. I just reach around behind me and ease it down and it works fine. Can someone help me understand what this 'flap' is called. Also, anyone have experience of this part misbehaving/failing.

[Alfieboy]

Nobody, anybody? Failing anyone on here having a fix or suggestion, I'll pop it into the dealer in the next couple of months when I put on the winter tires, as I don't want it packed away all winter under the hardtop without repair - we all know how that story is going to end next spring!

[Loren]

It would be best to find a shop with a PST2 or PIWIS tester and have them perform the Convertible top diagnosis tests.

Could be timing, could be potentiometers, could be microswitches - the tests would likely nail the fault(s).

[bskubish]

I have almost an identical issue, see my post also at members:bskubish. Let me know if you find anything out. I can see the screw turning for the flap, just my flap moves slow as heck. Thanks! Good luck...

http://www.renntech....915#entry185915

Edited September 28, 2010 by bskubish

[JeTexas]

The top is programmed to perform a series of movements. Each movement is activated by a microswitch that notifies the computer that the previous movement is finished and it's time for the next one.

The flaps you're talking about have screw drive motors. You can grease the screw drive, so that the nylon bearing moves up and down them easier and that should solve your problem.

The reason the top starts moving once you hand manipulate the flaps into place is that when you kick them into the correct position, it triggers the microswitch to tell the computer to activate the top movement.

I had to grease mine about a year ago. I haven't had any trouble since.

[Alfieboy]

Thank you, this is very, very, helpful. When you say grease, any specific products? With so much cab top material exposed to the inner workings, I'd hate to apply something that stains the cab top fabric.

[JeTexas]

Thank you, this is very, very, helpful. When you say grease, any specific products? With so much cab top material exposed to the inner workings, I'd hate to apply something that stains the cab top fabric.

If I remember correctly, I first sprayed it with some lithium grease, and that got it running again, but then I decided to take a little wheel bearing grease on my finger and slather it up and down that threaded screw drive. I don't think the convertible top itself actually touches it in any way.

[Alfieboy]

Thank you, much appreciated.

[bskubish]

Thank you! I also found a great article about it at : http://docwilenracing.wordpress.com/2010/09/22/996-cab-repair/