HELP!!!1990 C4 Convertible Top Problem

jejacobs7 · 08-08-2006, 06:41 AM

HELP!!! I went to raise the convertible top yesterday and something bad happened.
The top raised all the way up to the point where the front motors should've kicked in and locked it down...at that point I heard a "pop" in the back. Now when I push the switch I can hear a motor spinning in the back put nothing happens...the top does not lock in place and when I try to put it back in the down position it will only go about halfway.

As a side issue, I've heard of using the top in a manual mode. Is this possible. Assuming I can get the front locking motors to work, can I just loosen the back screws and manually lower and raise the top there while locking it in placd with the front motors or will the sensors not allow this type of operation.

My convertible top has sounded weak from the day I got it and I'd be more than happy to do it manually.

gduke · 08-08-2006, 03:59 PM

Ouch! I've had all kinds of problems w/ my top. It is a 1985 and is probably similar to yours. First, if your motors made a lot of noise and seemed weak they could be wore out. It also, sounds like maybe a cable snapped. Motors and cables cost alot of money and you do not want to opperate the tops w/ neither in god condition. My motors sounded worn and tired and the top quit workung just like yours did. So, I took it to a mech. and he replaced the controll module on the passenger side floor and the top worked. But, the motors sill sounded weak. And once again the top stopped half way up. So, I tapped on the module w/ a screw driver and the top worked again for a while, until one day on of the motors seemed to struggle, causing one side to come up faster than the other and the left bow broke, puncturing the top. It was the worn motors that were causing the problem in the first place. They drew too much current and caused a cold solder joint in the control on the passenger side floor.

So, don't make the same mistakes that I made. You can opperate the top manually by loosening the 19mm bolt on the transmissions. It sould explain how to do this in you owners manual. Also, you can opperate the windshield latches manually w/ a screw driver. There is a slot on both the right and left where you can insert a screwdriver and manually latch and unlatch the top. This is a real PIA. It takes forever.

What I did was permanently disconnect the trans. and motors and use the power latches to latch it to the windshield. Keeping the power lactches opperational and disconnecting the motors is what I'd recommend on a 16yr. old car. It isn't worth the amount of money to replace everything and by raising and lowering the top manually, it will never fail and you'll have the pice of mind knowing nothing expensive is going to break.

Gary

jejacobs7 · 08-09-2006, 06:34 AM

First of all, thanks. I agree that raising and lowering the top manually and using the power latches to lock it down is the best route. Disconnecting the transmissions looks easy enough. Is disconnecting the motor just a matter of unplugging some connectors or do I have to start cutting wires?
Also, how did you keep the power latches operational? Right now my top is at the point where the power latches should be kicking on to lock the front down. When I push the switch I hear a motor in the back spinning but nothing happens with the latches. Is is possible that there a microswitch failure and the front latching motors are not getting the signal to engage. Do you have any experience with this?

Hate to sound like a novice but this is my first p-car and my first trip into its guts.

drisin80 · 08-11-2006, 08:47 AM

hi-i had a similar problem, only worse. i recently snapped a b-pillar on the r side of the car. i will fix this over the winter, but wanted to continue use of the car through the fall. when the part snapped it caused the frame to be slightly out of allignment. i disconnected the transmissions as in the owners manual, and was able to raise and lower the top easy enough, but just like you, the power latches would not engage, even though i could hear the motors running. after some inspection i noticed that are a couple of switches on the top itself, close to the latches. the motor that raises and lowers the top is unrelated to the latching mechanism as best as i can tell. what seems to happen, is that when these switches in the top are depressed--by the top making contact with the window frame--- it signals to the latching motors to engage. in my particular case, since the top frame was slightly out of kilter, it was not seating fully with the window frame, and hence not engaging these switches. i found that the cure for this is to pull down on the top (from seated inside the car) to engage the switches, and then operate the rocker switch (tricky for one person to do, i used a cd case and my left knee for the rocker switch). worked like a charm. give this a try. ----tom

krauthead · 10:33 AM

When adjusting the upper transmission micro switch be sure it is in the open position. It is only there to stop the top operation should it travel too far. Aren't these tops fun! Tom is correct. Both microswitches on the front of the top frame must be closed in order for the locking motors to function. You might have to pull down pretty hard before operating.

gduke · 08-11-2006, 04:23 PM

Yes, Tom is correct. Both switces must be depressed innorder for the locking mech to work. You might need a friend to push one of the switches while you push the other and opperate the dash switch. Also, you can disconnect the cables from the motors and transmissions. The is a clip you can remove to disconnect the cables. I'm not sure if you have to adjust the trany micro-switches.

Tom, my frame was out of alignment too, from the B-piller snapping.

Gary

gduke · 08-11-2006, 04:30 PM

After disconnecting everything and raising the top manually, if the locking switches don't make contact, you can adjust the top foreward by making an adjustment to the I-bolt beneath the transmission.

Just make small adjustments, only a few turns each time and make the same adjustment on ea. side.

Gary

drisin80 · 08-15-2006, 05:24 AM

hi gary- left you a pm, but thought you might have missed it. how did you fix the b pillar???--i am looking for the easiest way out of this mess. also--i am looking for the cause of the breakage--it snapped when the top was about half way up. my current thinking is that something happened at the transmission on that side--either failure of that part or more likely failure of the cable, causing the other side to continue to pull and thereby fracturing the pillar. does this make any sense???? thanks---tom

jejacobs7 · 08-16-2006, 09:18 AM

Well, thanks everyone for your input on this mess. I tore into the roof mechanics and found that two of the three "eyes" ( in which the screws that mount the right side roof transmission into place go) are broken off and the whole transmission itself is swiveling back and forth as I manually open and close the top.

Tried closing the front microswitch on that transmission but still couldn't get the front latching motors to run (I've tried with it open also).
I'm gonna try holding the microswitches on the front latches closed while someone else pushes the dashboard switch to see it that works.

Not sure where to go from here. I've located another transmission but I hate to pay for a working one whne I've decided that even after I figure out what's up with the front latching motors I'm going to keep the rest of the roof in "maual" mode.

gduke · 08-16-2006, 01:44 PM

I also had some broken wiring near the bow that broke. That may be something to check. Just an idea.

Gary

JWPATE · 08-19-2006, 11:48 AM

Hi,
About a year ago I busted the driver side B pillar while attempting to raise the top on a 90 C2. At that time, you could still get the replacement part from Porsche, but lots of $$$. I got a used one from a wreck.
The busted pillar problem is common. It results from one or the other motor/transmissions not pulling its load and the good side motor is left with the entire load at a poor angle........the pillar on that side breaks.
For those about to start this repair. First, there is a good factory bulletin on the subject, with step by step directions. It is not necessary to remove the entire top. You can get in there by folding back the affected side top sections. The upper attachment of the b pillar to top bow will require some metal cutting and drilling, but no welding is needed.
For any member about to start this job, just drop me an e-mail with your fax number and I will dig out that instruction sheet and fax it to ya.
James

Sr. Parts-a-Lot · 08-28-2006, 09:16 AM

if you need the relay control box wich is most of the problem everytime, i have a new one for $200. plus shipping.

bodadjuster · 10-01-2006, 02:14 PM

hey james , the b pillarr jus broke on my c2,,,, could you please fax me the informationu have onhow to remove it,, thankyou,,,myfax is 732 749 3246

steve

JWPATE · 10-01-2006, 02:21 PM

Steve,
As I learned when another member needed the info. a week or so ago, there really is too many pages to fool around with my slow fax capability. If you will give my your street address, I will print the pages out and mail them to you.

James

dhf · 09-15-2008, 06:28 AM

Quote:

Originally Posted by gduke

Ouch! I've had all kinds of problems w/ my top. It is a 1985 and is probably similar to yours. First, if your motors made a lot of noise and seemed weak they could be wore out. It also, sounds like maybe a cable snapped. Motors and cables cost alot of money and you do not want to opperate the tops w/ neither in god condition. My motors sounded worn and tired and the top quit workung just like yours did. So, I took it to a mech. and he replaced the controll module on the passenger side floor and the top worked. But, the motors sill sounded weak. And once again the top stopped half way up. So, I tapped on the module w/ a screw driver and the top worked again for a while, until one day on of the motors seemed to struggle, causing one side to come up faster than the other and the left bow broke, puncturing the top. It was the worn motors that were causing the problem in the first place. They drew too much current and caused a cold solder joint in the control on the passenger side floor.

So, don't make the same mistakes that I made. You can opperate the top manually by loosening the 19mm bolt on the transmissions. It sould explain how to do this in you owners manual. Also, you can opperate the windshield latches manually w/ a screw driver. There is a slot on both the right and left where you can insert a screwdriver and manually latch and unlatch the top. This is a real PIA. It takes forever.

What I did was permanently disconnect the trans. and motors and use the power latches to latch it to the windshield. Keeping the power lactches opperational and disconnecting the motors is what I'd recommend on a 16yr. old car. It isn't worth the amount of money to replace everything and by raising and lowering the top manually, it will never fail and you'll have the pice of mind knowing nothing expensive is going to break.

Gary

If you go the route of manually raising and lowering the top and use the motors for locking/unlocking the top, what are the procedures for synchronizing the lock down motors. I have this problem on a 1990 Carrera 2 cabriolet.

drisin80 · 09-15-2008, 08:45 AM

very simple to disable the use of power for raising and lowering , while maintaining usage of the power lockdowns. simply disconnect the transmissions by loosening the bolts through the plastic covers in the trim in the back seat areas on left and right. this disconnects the top from the motors. as for the locking motors, you need to do nothing. what signals the lockdown motors to engage is a little switch that engages the top of the window frame. if you look at them closely you will see these one on each side (a little rounded thing as i recall). if these are engaging properly when the top is raised and seated against the windshield frame, then when you operate the switch, the motors will run to lock or unlock. this signal seems to be independent of the raising and lowering motors. i have operated mine in this fashion after breaking a b pillar two years ago, and would not think of reconnecting them unless trying to sell the car. it is just as quick to do it manually, and there is no danger of breaking the top. if your motors do not lock and unlock when the top is seated against the windshield frame, then you may need to adjust the top to allow it to do so. mine is a little tight, and seems to seat better if the rear window is unzipped. i then lock the top down, and zip in the window. lol tom

bigchillcar · bigchillcar's Garage

hmm..scary thread.not sure where mine fits in the 'future problem' scenarios described here, but every once in a blue moon, i've had to 'coax' mine slightly with my hand to get it to release to put the top down. anyone's ever seem to just stick a little? sign of a motor weakening? never seems to have a problem raising itself to close.