Convertible top will only open half way.

A new chapter! Yesterday I got into my 996 Cabriolet to run some errands and since it was such a nice day I decided to put the top down before heading out... as the top began to open and move back I heard a load snap! It continued to move but stopped half way! I pushed the closed button and then tried the open button, same scenario but without any noise.... It just will not go beyond the half way point. I have searched various forums and googled the problem but no solutions to be found. And pointers appreciated.

My first suggestion would be to check the hydraulic fluid, but since you heard a "loud snap", It could be something else. Perhaps one of the ball-ends on the cables ? This would cause an odd wrinkle, but should not prevent the top from closing. Is it making any sound when you try to close it? Any other details or pics?

I will post a picture this afternoon. The last couple of times I operated the top the red dash light would not go off... Perhaps a sensor?

Last night I left the top in the half open position and the clam shel was open. This morning when I took a look at the car the top had collapsed into an almost closed position (fully open) with the clam shel in the open position. Now the top will not move in any direction!

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The "collapse" back to closed is no big deal. Slow bleed-down of the hydraulics. I assume when you press the button, nothing happens. No sound, no movement. That would indicate a microswitch is not being made. There are many of them, so you'll need to start some more advanced diagnostics. E-brake microswitch, clamshell motor position, side flap position, windshield "hook" receptacle, etc. Google "porsche 996 convertible top microswitch locations" for some good links. Check here for some basics: https://www.pelicanparts.com/techart..._Mechanism.htm

I one heard a loud snap on my convertible. I found a broken (snapped in half) aluminum bar that connects at the back of the car. So could be something like that.

Carl. When it rains, it pours! I've owned many convertibles and I have to say that it's never fun tracing the problems with the automatic types. Those things have sensors that monitor resistance and if something is not right, they'll stop or return to the original position. Sometimes, it will make ya cuss and long for the old manual systems. Personally, I would put the top in service mode and begin the investigation. Pull out the bright flashlight and look for all things obvious. If you heard a snap, then IMHO, it's not hydraulic related. Something in the mechanism presented resistance and broke. You can always try cranking it manually.

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Just be aware that if you crank in manually, a recalibration by someone with the right type of computer system will be required. Also, it may require a repair to the clamshell motor mechanism.

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Thanks for the heads up Frisbee and Nutty Proffessor, I did read that on a couple of other posts. I disconnected the clam shell motor from the controller and supplied 12V dc to it. If you hook up the positive from the battery to the green wire and negative to the gray wire on the clam shell motor, the clam shell will open. Reverse the polarity and it closes. I manually stowed the top and then closed the clam shell using the above method.While messing around with the top today I discovered that I have a broken passenger side main support and a twisted main bow on that side as well. That was most likely the loud "snap" i heard the other day. I drove to the storage unit and picked up and installed the hard to so that for the time being I can drive the car until i can get the various parts that I''l need for the repair. Oh and I also found a good size puddle under the driver side rear tire. Clear and oily, i suspect that its hydraulic fluid for the drivers side actuator. What a mess!! Cracked casting for convertible top mount. The top bow on the passenger side is also bent and twisted. $$$ Fortunately the car came with a factory hard top that I'll be using until I can collect all the parts needed to make the necessary repairs.

You are being tested Carl. Hang in there!!

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You are correct Jim. With the engine rebuild behind me, see https://rennlist.com/forums/996-foru...mix-issue.html I was feeling that it was time to work on my neglected F150 pickup. Rear brake calipers, cloudy headlights, inoperable door actuators etc. Well my 996 must have felt neglected! That car is truly a very demanding job mistress!

I had some time this afternoon to dig deeper into the non operational convertible top. The replacement mounting plate that I purchased on eBay arrived and we�re off to the races! Cracked aluminum mounting plate on passenger side. What a mess. Another view. The top was to heavy for me and my wife to lift off of the car and the neighbors were not home. Help will come tomorrow.

My theory is that one of the hydraulic actuators was leaking and low on fluid which caused the top to twist while I was trying to open it. Loud snap!! I did find a puddle of clean oil under and in front of the drivers side rear tire. Waiting on a small retainer to come from porsche and a couple of oil seals, then I�ll rebuild the actuators.

I spent some time installing the convertible top with the new to me mounting plate from eBay. I rigged up my lift with a strap to suspend the whole convertible top assembly from and lowered it in place slowly until everything lined up and I could reinstall the mounting bolts. Though not terribly heavy the convertible top weights around 140 pounds and is awkward to handle. Top suspended from a strap between lift pistons. About to be lowered. Voila! The hydraulic pistons have not been rebuilt yet but with a 12volt battery in the back seat I can actuate the clam shell and manually raise and lower convertible top. I�ve learned how to manually secure the front latch should I need to batten down the hatches... Though I do have a hard top that I could use, just love driving with the top down! Especially during this unusually warm September that we just had. The warm temperatures during this past September have broken all records!

I received the rebuild hydraulic cylinders last week and I just installed them on Friday. Cabriolet Hydraulics in Florida did a Great Job! Excellent communication and quick turn around. They rebuild both cylinders and polished the scored piston rods to look like new. Rebuild �kit� from Cabriolet Hydraulics. Comes with new seals, hydraulic fluid and instructions. The installation was easy, just follow the included instructions. While there I also replaced the missing bolt/stud that attaches to the bow and provides one of the connecting point for the cable between the bow and car. I never could find the part on the Porsche parts fiche but lucked out and found the perfect part on eBay! 8mm Ball and 5mm post. The nut was still in the bow. Tricky to get it threaded back on but doable. I tried to calibrate the to using the Durametric software but it just was not able to accomplish the task. It sees the top and I could clear the faults but the program hung up repeatedly during the calibration mode. i will go and visit our local independent Porsche mechanic Pete Martin at Stuttgartgart Motorwerks next week and hopefully have a functioning top once again. I miss it!

Looks like a nice kit from CH! Hopefully the installation goes smoothly, Lake Lure is in 2 weeks!

CH has mine now. Should have them back this week. Can't wait for my top to work properly again.

After spending a good part of one morning trying to get my Durametric to talk to my top I gave up and took the car to my local independent mechanic Pete Martin at Stuttgart Motorwerks. He hooked it up to his PIWIS computer and cleared the faults and tried to get the top to go through it�s motions and synchronize. We spent the better part of two hours trying various ploys but the diagnosis that he arrived at was that the front opening motor/mechanism was inoperable. Strange be a use it had been working before. I may have done something when opening the top in the manual mode... Along the way he noticed a hydraulic leak, my fault, loose banjo bolt, and a missing circlip on one of the small rods attached to the clam shell. It so happened that I had a �spare� latch assembly... long story. My marching orders were to go home, replace the latch assembly and top up the hydraulic fluid and then report back to him. Pete was busy with other customer cars for the next couple of days and I being impatient went ahead and cleared the codes and ran the synchronization program at home using my Durametric software. This time it worked! Sort of, the latch would release, clamshell would open along with the top. I then tried opening and closing the top using the dash button and had mixed results. The clamshell would not latch properly when closing. My dear wife noticed that the two side flaps were not working in concert. The passender side was lagging behind the drivers side and hanging up. I disconnected the harness from the passenger side and applied battery voltage to the actuator motor and moved the gear assembly and flap until it was in the same position as the flap on the drivers side. Voila! I now have a functioning convertible top. I still have a red warning light that hopefully will go away once I revisit Pete and he can hook the car back up to PIWIS. A working convertible top just in time for the cool days ahead....😉

Got my cylinders back from CH today and installed them. Installation went well. However, after cycling the top 6 or 7 times it still kind of bounces down which it had been doing for a while until the cylinders really started leaking badly. Called CH and he told me that this is common after time with the MK1 cabs with the first generation top pump. I thought this was due to just leaking cylinders. But he said that if once you repair your cylinders if this still happens it is the pump not working fully. So my cylinders were leaking but the bounce was also due to the pump. Thought he was going to tell me I needed my pump rebuilt, but instead he said there are new banjo bolts with smaller holes for the fluid to pass thru which will fix this. He did warn me that in time the pump will fail (which is why they changed the design for MK2) and need rebuilding. So this is a temporary fix, but could last many years. He's sending the new banjo bolts and I should have them Monday. Not cheap, $60 for the two, but if it works and lasts several years, worth it. I'll call him back and ask exactly why this works and what the new banjo bolts actually do. I wasn't listening too closely. I just figured I wouild follow up here and share this for anyone who might have this issue with the MK1 top pump. So if your cylinders are not leaking and your top bounces when putting it down, these new banjo bolts should stop the bounce until the pump fails altogether. And by the way, the bouncing is not good for the cylinders. I'll report back Monday

Thanks for the heads up Rolex, I�ll keep an eye on mine.

Carl, Sure thing. Spoke with CH just now and I asked just what issues the 1st gen pumps have. According to him these pumps have a valve that partially fails and alters the pressures which leads to the bouncing when putting down the top. The bouncing is also due in part to the overall loosening (joints, connections, etc.) of the top itself over the years. Supposedly if your top is very tight and you have a bad pump it won't necessarily bounce, and if you have a loose top and a properly working pump it may not bounce either. It's when the right degree of looseness in the top in combination with the pump going bad that will lead to the bouncing. The new banjo bolts have a restricter in them which alter the fluid flow and compensates for the failing pump. So bottom line is, if your cylinders are leaking, fix them period. If you have a bounce when putting down the top and your cylinders are good, get the new banjo bolts. The bouncing is not good for the cylinders and can cause them to start leaking sooner. At some point the pump will fail completely and then it's time to have your pump rebuilt. Apparently, the 1st gen pumps are no longer sold and have to be rebuilt or replaced with a rebuilt unit. Sorry if hi jacking post, just wanted to get this info out for others....

Not a problem, that�s the wonderful thing about this forum. Knowledge gets passed around and though you may not need the information just now, you know that if you�re the lucky owner of a 996, sooner or later you will... 😉

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Installed the new banjo bolts from Cabriolet Hydraulics. The bounce when putting the top down is gone. Along with the new cylinders the top is working great, very smooth operation and much more quiet. All set for convertible weather here in South Florida. Total cost was $555 for cylinder rebuild which included new fluid and copper crush washers, including shipping both ways. Then the additional $70 ($100 -$30) for the new banjo bolts to stop the bounce. They refund you $30 if you send them your old bolts. So $625 all in and my labor. Any time I can fix a major component on the 996 for under a grand I'm happy. Now hoping the pump holds up for a while before needing rebuilt.

I sure like the look of that 2 Post Lift, any chance on your giving us the type & model ? Thanks John S

John, it’s a MaxJax, the short model.

good evening Frisbee91. i hate was happening to me. i have restored a 00 Porsche 911/ 996cab. now that i got the convertible motor to work with Porsche fluid add its topped off correctly the convertible top works good opens ans closes. i also got new microswitch for top hook area so 1/4 windows work good. my problem is i bought the car with out the drive mechanism 996.561.021.03 so i found one cheap and installed it ( i do all my work). plug it and gave it a go. and nothing. clamshell does not open or close. it opens and closes manually only. when i press switch on dashboard i hear a motor sound and it times out. but clamshell won't open or close. i can't find who sold me the drive mechanism so i can't get my money back. so i opened the blue attachment to the motor and everything in there is complete,nothing broken. ( i even bought a repair kit just in case). so is it the mechanism motor working but not pulling its weight.?

It's difficult to say what the problem might be. First check the operation of the drive motor. Is it getting power and trying to move? The clamshell mechanism can bind up easily, so perhaps the motor is trying to move, but the clamshell does not move easily. More troubleshooting is needed.