Technical 500C softtop issue

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Technical 500C softtop issue

4SilverRings

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Hi There,
I too have a problem on my 500C soft top which may be more complicated than the ones I've read about up to now.
The softtop does not work properly anymore. it makes strange noise when opening, closing, randomly and does not close or open correctly preventing the opening of the trunk at the same time. When it doesn't open or close properly, there are souds like "clack clack clack clack ..." as if sprocket teeth or a never ending screw were jumping.
I sent it to Fiat as part of its overhaul and asked for a repair quote. 2600 Euros! I do not know why but they replace everything except the tissu itself. Guides, electric motor and so on!
With the crank tool it goes down or goes up very well. However, defrosting no longer works. I tried the 3 seconde hood reset procedure but without result. It never opens or closes at once. Fiat also tried re programming but without success.
I would need your help because I would like to clear the various elements rather than replacing everything and thus reduce the expense if possible. Is there any technical documentation that would allow me to understand the operation, to disassemble and possibly reassemble and see what is the problem?
Your help would be really helpful.

Thank you in advance and enjoy your ride,
 
Hello Typecastboy,

Thanks for the answer. Yes,I've tried that with no success.
 
Good evening Chris,
And thanks for your help.

Yes, I have power to the motor and yes, the motor moves.

Is there a way to check the mechanical with the gearing or the folding mechanism ?
 
Good evening Chris,
And thanks for your help.

Yes, I have power to the motor and yes, the motor moves.

Is there a way to check the mechanical with the gearing or the folding mechanism ?

Hi.
Didnt you say it winds up and down ok with the crank handle..?

That should be proof of the hoodmechanism..

Its the drive of that mechanism that seems lacking

Find out how linked.. or independant the crank and motor are ;)
 
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Hello Varesecrasy.
Yes, it will up go and down perfectly with the handle. It will even lock or unlock. Main problem is that it's not always the case in electric mode. It won't always go down till the end and then will try continue in making a strange noise like clac clac clac without moving anymore till I remove my finger from the button, then I'll have to disconnect and reconnect the battery.
And sometimes, same deal when going up. It will do exactly the same when arriving close to the end but it won't lock down.
 
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Though I don't know the exact mechanics of the roof (mine luckily works fine) this sounds like an end position switch off issue. If there are indeed switches, they may be bad or the connection broken, keeping the motor running. If the end position is recognized via high current detection of the motor, then the control electronics that does that may be at fault. Difficult to say without a circuit diagram which unfortunately I don't have.

Still does not sound as if it would need a complete replacement of nearly everything as suggested in the first post...
 
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It sounds like some part of the roof mechanism is broken or jamming.

As I understand it there are no limit switches or sensors, the whole thing is operated by the control module that lives near the roof motor and which has to 'learn' the limits of travel of the roof through the initialization procedure so it can stop the roof at the spoiler position and 250mm short of closing, likely detecting high current when the motor stops as Mike says.

These vids give some idea of the complexity of the operation;


https://www.youtube.com/watch?v=czivkQxdSg8


https://www.youtube.com/watch?v=SV-MbF1IPRs
(This one's hard to watch but might have some additional detail)
 

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Ok, thanks for that first video, it helps a lot to see all the parts, though it goes a bit fast over the important moments where one could try to understand the intricacies of the mechanism. I had seen the 2nd one before - that makes you feel as if you're in a tumble dryer...
I'm afraid I have to partially withdraw my last comment about replacement. It may not need all new mechanics, but as often, the spare parts probably come as a complete set only, driving up the cost. And in this case, labour cost is likely to play a major role.
 
Ok, thanks for that first video, it helps a lot to see all the parts, though it goes a bit fast over the important moments where one could try to understand the intricacies of the mechanism. I had seen the 2nd one before - that makes you feel as if you're in a tumble dryer...
I'm afraid I have to partially withdraw my last comment about replacement. It may not need all new mechanics, but as often, the spare parts probably come as a complete set only, driving up the cost. And in this case, labour cost is likely to play a major role.

The research has at least given me a better idea of how the whole thing works - I had no idea the cables ran back up the opposite side when the roof is retracted.


Yes, the sliding parts appear to come in sets, but at least in separate left and right sets. Horrendously expensive sets too. Having said that, If I were replacing worn/broken parts on one side I'd want to do the other side as well. Looking at those vids I wouldn't want to tackle the job myself. Given the probable labour cost It might come down to a question of fix the roof or sell the car!

My roof's seen a lot of use over the seven years I've had the car - I open it at the slightest opportunity - and it's certainly a little noisier these days. My wife's car's roof has hardly been used and its extremely quiet. I'd like to try to lubricate the running parts but I don't know what with or how best to apply anything.
 
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