After digging deeper and deeper into my convertible top problem I finally gave up, removed all the power top hardware, and converted it to manual operation. I’d like to thank Shiura from YouTube for main idea presented here.
Removing all the hardware (15 pounds worth) and putting the top up and down manually is easy enough, but two problems will remain. How to secure the convertible top lid and how to get rid of the error messages.
Materials used….
2 1” Adel Clamps (
www.aircraftspruce.com
)
MS21919-DG16
Marine Heat shrink (Marine is thicker and has an adhesive inside so it can be formed to shape) Harbor Freight
Step drill (Harbor Freight)
The trunk is used to hold down the convertible top lid. So, you have to open the trunk while you’re putting the top up or down.
The Adel Clamps are soft aluminum so they can be reformed with pliers. They need to be opened up and trimmed to engage with the trunk. The 90 degree end needs to be opened up about 10 degrees to clear the rubber bumper/bolt and the rubber at the bolt end of the stopper needs to be sanded a little so it has clearance to turn. I started out with Adel clamps that were a bit too big, so yours will probably look better than mine.
The heat shrink can be formed into the cushion shape while it’s still hot with pliers and the adhesive lining will hold the shape. The hole is too small so use the step drill to open it up to fit the bumper bolt.
My car needed one side to be a little longer than the other to hold the lid firmly. It’s probably a good idea to get extra Adel clamps in case you need to make a few to get a good one.
The second issue is the error messages caused by the car not seeing the hardware. The solution is to put a jumper wire in the plug that goes in the drivers side transmission. Put heat shrink over it and squeeze the end while it’s hot to seal it. There are three pins and only two need to be connected as shown in the picture. If you get it wrong you won’t hurt anything, but you’ll still have the error message. This tells the car the top is up so the windows will always drop when you open the door. You might have to put the windows all the way up and then keep holding the switch up for a few seconds to reset the window system. The plug is easiest to access with the top all the way down. This cleared any error messages for me. I didn’t do anything to the microswitch above the windshield.
I’ll offer some advise if you want to keep the power top.
Check the resistance of the electric motor immediately, just unplug it and put a multimeter across the two pins. A new one is 26 ohms. My original was 0.6 ohms which means most of the windings were shorted. It still seemed to work okay, but it must have been drawing a lot of current to run. The current draw goes up as resistance goes down and this will eventually cause the fuse to blow or the relays to burn out even thought the motor still works.
I started look at the power top system when I got an error message (top not in limit position) which I think was due to the motor being too weak to get the top all the way down. I got the new one from HT which seemed pretty good. You have to rip the pins out of the old plug and reuse it. Take a picture before you pull the pins!
I got new cables that go from the motor to the transmissions from HT. They were garbage and came apart almost immediately. Reuse your original Porsche ones.
Remove both transmissions and open the up and inspect them. Make sure they have the updated black plastic gears inside. The original white ones crack and fail. One of my transmissions had a broken case that someone tried to epoxy back together and the repair had failed. JB weld worked well to repair it. New transmissions are $$$$.
Replace the bushings on the arm the runs the top. Mine had a lot of play and that will make it difficult to adjust the top operation.
When you reinstall the transmissions align the marks to start with, then install the arms and use the digital level app on your phone to adjust the passenger side to exactly match the drivers side. The shop manual has us measure down from the lid, but digital level is much more accurate and easy.
All in I probably spent 10 hours messing with the power top system. The system is well engineered and will probably work well for long time if you go through it all, but once I realized how easy it was make the little hold downs out of Adel clamps I just went manual.
Here’s all the pictures I took…..
If it’s possible to turn all of the auto formatting stuff off then please, for the love of god turn it all off.
