dotcomhusker

This forum has been a lifesaver in all areas in the past, but especially so when it comes to this pesky targa roof so I thought I'd ask for some help from the 993 targa owners out there.

The other day i was opening the glass roof and heard a bit of what sounding like 'binding'. The roof was all the way open but one (maybe both) of the motors was still trying, it seemed to continue opening an already open roof.

When I got home later and tried to close the roof, it would only move forward about 3.5 inches or so. The motors still work, its just that they only move the roof forward and backward that 3.5 inches now. Today I took out the rear panel, removed the red tabs that engage the motor with the cables, used the hex keys and did just over 3 full rotations counterclockwise, closing the roof about 3 inches more manually. Put the red tabs back in and was able to close the roof the rest of the way with the switch. Tried this several times with the same result.

Any ideas?

Thanks in advance for any help.

Mike J

When you did this, did the motors stop automatically when the roof was closed, or are they still trying to close the roof but the roof is closed?

The motors "count" the number of rotations for the close/open cycle - there are indexed sprockets inside the driver portion of the motor that "count" the number of revolutions the index gear has turned that drives the cables, and when the count is done, it hits a microswitch that tells the controller the the roof is either fully open or closed. Both motors are supposed to be synchronized as well, so both should shut off when the roof is open or closed.

If you pull the pins out and rotate, you can change the position of the roof to this counter. As far as I know, its solely this count that gives the signal to the controller on the roof position - there are no microswitches that trigger on the roof itself when its open or closed. What you have to do is pull both pins, manually either fully open or close the roof, and then operate the motors (with the pins out) until they also stop. they both should stop together. Then push the pins in so now a fully open roof for example corresponds with the motors running to their limit fully open.

The most important position is the closing - to make sure that both motors stop precisely when the roof is fully closed, and not before or after. The open cycle does not matter as much, if the roof is not fully open by 1/8" it does not matter.

Problem is, you have to do some disassembly and figure it out for yourself, its no-where in the shop manuals or documentation. I understand they used to explain some of these procedures in the classes given to the Porsche techs when the car was introduced.

Cheers,

Mike

dotcomhusker

So, from all the way open:
1. Use the switch to close it and it only closes about 3.5 inches and then stops. The motors stop as well.
2. I then pull the red tabs and advance both motors at the same time, about 3 full rotations, which moves the glass forward about 3 more inches.
3. I then put the tabs back in and use the switch again and am able to get the roof to close all the way. The motors stop when the roof is closed and the deflector comes down as normal.

I will try to synchronize the motor to the position of the roof as you outlined. Somehow I knew it would be you that responded. I have plastic-covered printouts from your pcarworkshop site in my notebook and it has been invaluable. Whether this ends up fixing it or not, thanks for everything you've done, Mike.

-jerry

dotcomhusker

Ok, so just tried what you'd suggested. And from re-reading your post, it sounds like those motors, with the pins out, should stop. I advanced the roof to all the way closed, pulled the pins, and used the switch to continue the motors, but they didn't stop they just kept running. Same thing in the other direction. Sounds like this isn't normal, right?

Mike J

Hmm - I thought they should stop in each direction eventually. The thing I cannot remember now is if you pull the red pin, does that also disconnect the motor from this trigger mechanism that stops the motor.

You can take the top off ONE of the motor drives and have a look at the mechanism. When the motor is spinning, you should be able to see how the microswitch is triggered - which sends a signal to the controller to stop the motors.

My apologies if I am a bit rusty here - sold the Targa last year, and its been a few years since I have been into those mechanisms.

Cheers,

Mike

stairmasterman911

just had my roof worked on by my guy at TPWS in Austin... he semi-jokingly said he tells targa owners to throw a hundred dollar bill in the glove box every time you open that roof. you'll need it later. apparently the previous owner of my targa opened it about 15 times before i got it...

Mike J

I loved my Targa - great feeling while driving, fantastic opening when its open, but what was one of the main costs when I sold it? The cost of repairs for the roof - and I had an almost brand new roof that was only 5 years old from the factory (long story if you do not know it). However, to get it to that point cost a LOT of $$$.

So enjoy the roof for sure, I am totally jealous of the light and the open feeling - but I am totally happy about the avoidance of any costs to repair that sunroof...lol!!

Perhaps the next owner will reap the rewards of all the work and parts I put into that roof. If he does, great for him, but if it goes wrong.....

Cheers,

Mike

mgianzero

I saw Mike's procedures regarding resetting the targa top. Mike is truly one of the experts here.

I do have one comment to add. I believe that if you are truly trying to "reset" the timing for when the glass top motors start and stop, you have to complete REMOVE the left (driver's side) motor from its mount but KEEP its red tab in place. Then you pull the tab on the right (passenger) side motor to manually move the window to where you want it. This allows you to set the microswitches to the exactly position you want the glass to move. If you simply remove the tab on the driver's motor, then the driver's side motor never spins the gears which trigger the microswitch.

You must be certain that the two glass top cables are in synch with each other before you follow my procedure. Unless the cables slipped out of alignment with each other by binding the glass in the tracks and causing a gear to skip, they should be in good alignment with each other. NEVER REMOVE BOTH MOTORS SIMULTANEOUSLY FROM THEIR MOUNTS unless you really know what you are doing. This will cause the two cables to lose their position with each other and the window top will most likely bind in the tracks and can cause further damage to the cables and/or motors.

This is my procedure to reset the timing of the glass top to the microswitch timing.
1) Pull the tabs on BOTH motors while both motors are still mounted.
2) Place a hex key in either motor and hand turn while assisting the glass top with your hand (it keeps the cables from experiencing undo stress while turning manually. This can lead to cable kinking.) The best position to place the glass top is just after roof closes but BEFORE the wind deflector starts to close.
3) Remove driver's side motor (keep tab in place)
4) Close the top using the electric switch to the point where just the top is closed and wind deflector not activated. (You know this by holding down the close button until it stops turning motors. Then hold it in close position again and it will turn motors just another few turns - this is the wind deflector movement. Then open again until motor does a few turns to open the deflector only.)
5) Now the glass top and motor microswitches should be in synch again. Remount the driver's motor and install the red cap.
6) Test the full operation of the top. It should be "fairly" close to where it should be. If the timing is slightly off, which is common, either the window deflector will not close completely or it binds the glass a bit to where you may here some window crackle or even motor skip a tooth in the worst scenario. Then you simply repeat steps 3-5. But turn the passenger motor manually slightly clockwise to loosen the wind deflector, or counterclockwise to close the deflector more.

Hope this helps. You can refer to the TSB titled "Noises from the Targa Roof Area" under subsection "1.3 - Eliminate the play in the wind deflector drive cables." You can find this on Mike's website pcarworkshop.com under 993->TSB's for Targa subsection.

Hope this all makes sense -

Marc G.

Mike J

Ahhh, thanks Marc, very well said. I think the technique you are describing is essentially put the roof manually into a certain position, say the main roof closed but the visor up, then let the motors run to the same position, and then lock the motors to the cables and try it. If its not quite perfect, rinse and repeat?

I cannot remember this, is it the passenger side motor that has the microswitch for open/close?

You stressing not to remove BOTH motors at the same time is bang on - you will lose the alignment, and we both know the fiddling it takes after that to get it all back in position..

Cheers,

Mike

dotcomhusker

Ok, so an update, and it's not so good. I went through the steps of getting the stop points correct and after reassembly, the driver's side was sticking while the passenger's side was moving and the gears slipped a couple of times. Even with the tabs out I couldn’t get the roof to retract with the manually because the of the driver’s side binding. I stopped what I was doing. And, against everyone's advice, but since the cables were, it seemed to me, out of sync anyway, I removed both motors to see what was going on. I've got the roof so that it looks closer to symmetrical in terms of closure, but not all the way there yet. The wind deflector on the driver's side is almost all the way closed but on the passenger side is up higher which tells me they're still out of sync.

So the million dollar question... how does one sync the cables with the motors off?

Mike J

How do the cables look? The reason I am asking if they skip, the cables themselves can get marked/scored,and now you have a potential weak spot on engagement between the gears and the cables.

If the roof is not straight, that means the motors are not at the same spot on their respective cables - so you need to move one motor or the other. I think you have an idea which side needs to be shortened - sounds like the passenger side is longer than the driver's side. Again, its been a while and Marc is fresher than I at this - I think if you keep one motor bolted down and the pin in (drivers side), you can pull the pin on the free motor (passenger side) and use the key to turn and pull on the cable to shorten it, and then lock it to the motor.

If you look closely at the motors (especially if you take one apart) you can figure it out - its just picky work to get it right. Hopefully your cables are in good shape.

Cheers,

Mike

mgianzero

Yes, that's the way I do it. Actually, once you sit down and really study the somewhat abbreviated version of the Porsche TSB on this, it makes sense. The most reliable position to place the glass in to synchronize the glass position to the motor micro-switches is to position the glass top closed but keep the window deflector completely open.

The microswitches are on the driver's side motors. If you pop the red tabs that engage the motor shaft with the cables then BOTH the cables will NOT move AND the microswitches will not be activated. Would be nice if there was a way to reset the microswitches to the cables WITHOUT removing the left motor completely. I guess this is one way to make certain you do not inadvertently misalign the motor position to the glass top.

Yes, once you misalign the glass top from right to left, I found really the ONLY way to be certain that the cables are perfectly re-aligned is to completely remove the glass top and manually time them again by getting both sides to raise the axel pins at exactly the same time. Otherwise you are always guessing whether the top is straight or not. My feeling is if it's not EXACTLY aligned right-to-left, you will never get everything else to work properly.

Mike J

Marc, can you adjust the position of one motor on the cable relative to the other to do the alignment (ala my description in post #11)? The may have to pull the gear to get it down to one tooth on the gear vs one notch on the tab.

mgianzero

Not quite sure I am following what you are suggesting here Mike. However, I know that the most assured way of aligning these cables to each other (i.e. side-to-side) is by removing the glass altogether. You'd be surprised how small a movement one gear tooth notch would do. You won't even notice it until you remove the glass as a check. The window "may" slide okay, but with the changes in temperature and movement of the top with driving, the top can eventually bind. Unfortunately, Porsche does not leave much play side-to-side to account for a slight misalignment.


You might try this trick as a compromise if you really want to realign the cables and don't want to remove the glass top. But I strongly recommend you do this with a second person assisting.

1) Disconnect and remove BOTH motors since we know they are misaligned. See if you can stand up inside the center of car and jiggle glass top side-to side to see if it goes back into better alignment. If you can (and driving pins are down - that is the glass top is lowered below back window) try to push the glass top forward and backwards until the movement is reasonably smooth. DO NOT FORCE IT. Also, you CANNOT do this if either axel drive pin is raised, even slightly.

2) If you still cannot get the glass top to slide easily, try reconnecting just one motor (passenger side is best) and, with red tab pulled, have a second person crank the motor with an allen wrench while you assist in pulling or pushing glass top from inside the car. Be careful. Do not force. Also, if you notice either of the cables starts to bend where the other motor (driver's side) was mounted, stop. You do not want to kink these cables. If you do, you're onto a complete new cable reinstallation. (We may have to replace these cables anyways if they are too stretched, chewed or kinked. We'll talk more about this if we get to this point.)

Marc G.