The convertible top on one of my cars stopped working a couple days ago. The top was stuck closed (up).
First I checked the fuses: B6 and D3, then I pulled out and re-seated the relay (red arrow in this pic:
http://cdn4.pelicanparts.com/techarticles/Boxster_Tech/72-BODY-SmartTop/images_med/Pic1.jpg)
Next, I checked the front latch, there are two micro-switches in there. One drops the windows, the other is for the Top Relay. The latch is held in place by two screws covered by the 'alien eyes'.
After all that looked good, the rest of it is in back, under the top. I had to get it open.
The components back there are the motor, cables, transmissions and control arms.
Pelican Parts has an excellent article on that, so I will not go into further detail. Here's the link:
Porsche Boxster Convertible Top Repair - 986 / 987 (1997-08) - Pelican Parts Technical Article
I decided that for now (and probably forever), I will operate the top on this car manually instead of electrically. It's simple, safe, and functional. If you remove
all the unneeded parts, your car will be about 15 pounds lighter. If you want to restore function later, it it not hard to re-install the required parts.
Here's the video:
Having done this, the clamshell is no longer secured down. It may rattle when you go over bumps, but I found that it does not lift at speed, and the top remains secure when you open it. I do recommend that you use a method to secure the clamshell just for aesthetics and having the job done right. Woody used a trunk latch and cable as shown in his build thread and here:
http://986forum.com/forums/performance-technical-chat/61665-manual-roof-downgrade.html
Eric G used some aftermarket latches:
http://986forum.com/forums/boxster-general-discussions/43235-why-i-converted-manual-top.html
I intend to use the trunk latch method on mine.