996 Cabriolet Clamshell Drive Assembly Problems

I have a 1999 996 Cabriolet, and have a few questions about the clamshell drive assembly. I've recently replaced one of the hinges because I had a broken arm on one of them (probably due to interference between the clamshell and an aftermarket rear wing, which I've now removed). I've reset the potentiometer and have confirmed that I have the full range of motion by manually opening and closing it, and the latch closes completely when it's fully down at the end of the full range of motion. However, I have a problem I don't know how to fix, and I'm hoping someone can point me to the procedure I need to use. When the clamshell is fully closed and latched, the microswitch that is supposed to active when it's fully closed is not pressed. I tested the microswitch, and it does work as expected. The problem is that the metal mount never goes far enough to make contact with it. There's about a full centimeter between the metal mount and the microswitch. Does anyone know the procedure to line this up correctly? I've attached a picture of the assembly, but this picture that I took is in the fully open position (the only way I could get a clear picture). I've added red arrows to the two parts that should make contact, just to clarify what I'm referring to.

Sounds much more like a setup issue than anything major. If the clamshell is going through the full range, the latch is fully closing and the microswitch itself tests fine, then the switch is probably not the problem. The more likely answer is that since the hinge change, the linkage or drive arm is just no longer arriving in quite the right place to trip it. A 1cm gap is too much to be one of those “close enough” things, so I would not start bending the tab or trying to fudge the switch. That usually just hides the real issue and creates another one later. To me it sounds like the clamshell is mechanically getting shut, but the system is not seeing the exact fully-closed position it expects. That is usually geometry, not disaster. Frustrating, yes, but fixable. 996 Carrera Convertible top Calibration Just completed repairing and refitting the clamshell drive unit on a 1999 Carrera cab, set the potentiometer for 6.2K ohms, cleared all faults with durametric, roof opens to halfway point, then sets operation timeout fault, flashes warning indicator and ceases operation. My question to anyone who... www.renntech.org Calibrating Convertible top - Rennlist - Porsche Discussion Forums 996 Forum - Calibrating Convertible top - I replaced the left cylinder due to a hydraulic fluid leak on my 2003 C4. I topped off the fluid in the pump reservoir connected the hydraulic lines then bleeding all the air out of the hydraulic system BEFORE I installed the hydraulic cylinder and... rennlist.com Calibrating top with durametrics. - Rennlist - Porsche Discussion Forums 996 Forum - Calibrating top with durametrics. - Tried to get everything back in sync using my new durametrics software. Reset actuation, cleared all fault codes. The top will go up than down all the way except the clamshell stops about 2 inches from closed. No movement from side flaps or... rennlist.com

I’d go back and compare both sides carefully, as I’d expect this to come down to one of four things: hinge not sitting quite right drive arm one notch out linkage adjustment slightly off switch bracket position having moved

"Linkage Adjustment" is something I'm trying to find more about, but I don't see anything in the shop manuals about it. The cable that connects to the back latch has a threaded collar where it mounts to the main drive unit, but I'm not sure this means that it's adjustable, that could just be the way it's mounted/secured. If it's not adjustable, the 'drive arm one notch out' is a possibility. Sounds like I would need to disassemble the drive unit and reposition that arm, correct? The hinges are good (after replacing one). There is no binding, they are free, and work as expected. When I installed the hinge, there was no perceptible room for adjustment where the hinge mounts to the body - it would only settle in to the car in one position. The position of the clamshell cover on top of the hinge is adjustable (barely), but it seems that adjustment is for maintaining proper gaps, it doesn't seem to affect the hinge operation. The bracket for the clamshell microswitch appears to be in its original position and undisturbed. I don't see a way to adjust that, or anything in the shop manuals about adjusting it. Section 61 81 19 in the Group 6 Body Exterior manual refers to the removal and installation of this switch, and there's no reference to an adjustment there either.

Well, good news. I took the car to a friend with a PIWIS and we got it fully operable. We didn't adjust anything on the rear lid, so I can't explain how (or confirm if) the latch got all the way to the microswitch for the rear lid because we couldn't see what was happening after we got everything back together and started testing the operation, but the PIWIS confirmed it was closed and latched, and all of the microswitches showed that they were in the correct position, but I still wonder if it was using the potentiometer voltage to confirm the closed position, or the actual microswitch indicator. FYI, we did have to re-adjust the potentiometer for the clamshell drive unit, because we could never do a calibration, so we had to set the potentiometer to a value that caused the voltage to exceed POT4 when fully closed. However, we still have a gremlin we can't identify. Although I can fully operate the top up and down, we can't run a calibration. Almost immediately after it starts, it says "limit not reached", and it doesn't give any indication of exactly what isn't at the limit. For now, he recommended that I use the top for a while as is, and see if the source of this eventually identifies itself.

Hi guys, I am new here. one side of my 996 clamshell is stuck down. The latch won't release on the driver side. I tried releasing it manually with the allen key but it still won't release. How can I release the stuck latch

Does this thread help. Read the 6th post down: S Thread '996 cabriolet clamshell will not open' 29 Jan 2017 Hi All So being a nice day with some sun I took the opportunity to take the roof down. Got to my destination and found that I could not close it again I have tried the manual way of closing but i get the same result, see the picture. Anyone know how I resolve this? Thanks shaunpr Replies: 13 Forum: Porsche 911 996 (1997-2005)