[gthang]

Is the highlighted caution usually found in a conventional automatic car?

Cheers.

[noopster]

Thanks Anshuman, that settles that, then!

I have a similar doubt to gthang's, sometimes on an uphill slope I let my (non-DSg torque convertor) AT stay in D without depressing the brake so that it stands stationary: find it really great, like an auto hill hold without paying for it

From what you've posted it looks like this isn't encouraged on a DSG, so will stop this pronto on mine as well!

[androdev]

I have no experience with DGS, but current gen BMW transmissions come with "neutral idle control" - I tried to find something similar for DGS but could not find anything definitive - and most seem to suggest you should shift DSG to N at stop signals.

"This is the NIC (Neutral Idle Control) function. When at a complete stop with brakes applied and gear selector in D, the transmission will shift to "neutral." A slight bump sensation (2-3 times) can be felt as the clutch decouples. When releasing the brake pedal the trans will reengage the gear, at times with a slight bump (surge) or hesitation. The strength of the bump-surge sensation will decrease as the transmission adaption takes place. Both conditions are normal at this time but are investigated for possible improvements. In sport mode this function is not active."

source: Problem w/ my '06 325i - Bimmerfest - BMW Forums

[vina]

Originally Posted by V-16

.....


Nope its a design issue.

Please note the only thing that fails is the Mechatronic and not the gearbox. The unit is changed on the same gearbox and all is hunky dory. Its an external box that feeds info to the gearbox on the changing pattern. A Dsg equipped car is a pleasure to drive, till it works. Gearshifts are extremely smooth and fast, faster than a manual and they adapt to the driving style of the person.

First, reliability is a design parameter, so reliability failure is a design issue.

Second, reliability doesn't only mean mechanical reliability - it means overall reliability including electronics.

Third, AFAIK, mechatronics unit houses the hydraulic controls as well (not just the electronics) so you can't say it isn't a mechanical failure yet,

Fourth, going by your own statement ("pleasure to drive, till it works") - it is an endurance aka reliability issue - still a design problem - but not an initial design problem.

[Sutripta]

Originally Posted by gthang

Attachment 860247

Is the highlighted caution usually found in a conventional automatic car?

Cheers.

No, not applicable. Though keeping ATF cool is a major design issue.
Your thoughts.

Regards
Sutripta

[gthang]

Originally Posted by Sutripta

No, not applicable. Though keeping ATF cool is a major design issue.
Your thoughts.

Regards
Sutripta

Not applicable for conventional automatic. OK.

Torque converter automatics have been around since before I was born, and I have not heard much of overheating issues with auto trannies. Which either means I dont get around much, or somebody has that problem licked. Either way, not something I have thought about much.

Coming back to topic, given that the previously mentioned DSG caution is not applicable for regular automatics, would you say that driving style for both can be the same?

Cheers

[Aroy]

The overheating in DSG is due to one of two clutches always slipping which is not there in the torque converter design. Thus the DSG should incorporate extra cooling for tropical and start-stop traffic duties.

Due to its design, in my opinion, it will always be a good practice to switch the DSG box to neutral for all but short stops, to prevent premature DSG failure.

[anandpadhye]

Originally Posted by noopster

I have a similar doubt to gthang's, sometimes on an uphill slope I let my (non-DSg torque convertor) AT stay in D without depressing the brake so that it stands stationary: find it really great, like an auto hill hold without paying for it

From what you've posted it looks like this isn't encouraged on a DSG, so will stop this pronto on mine as well!

Always, it's a choice between clutch plate and brake pads - what would you prefer to burn?

DSG makes it easier to burn the clutches (or cook the gear oil, or both), Torque Convertor makes it easier to cook the brake pads...he he he.

Whenever I drave an AT (torque convertor or DSG), I shift to "N" whenever I can - to save the gear box (just in case). It's easier to deal with brake pads replacement than any servicing of the AT - IMHO.

[.anshuman]

DSG comes with overheat warning, how many of those who have participated in the poll have seen the warning? Without any data being available, is it fair to blame the design?

Even if it is a MT car, i never use the clutch to hold the car on an incline, i only slip the clutch when it is absolutely necessary.

[Swanand Inamdar]

So, again there is no full proof method of using the DSG. Well, thats fine. I guess, to each his own driving style.

What gets my goat is, when in countries like the US or Singapore, where the failures have been brought to notice, the company has been prompt in admitting the issue and getting the box replaced. Heck, even the warranty has been extended - as pointed out by the excerpt, Vb-San posted.

Why are we Indians been taken for a ride then? Why cant they admit that and do the same here? Specially when, this isnt a small market for any automotive company by any standards.

[nawalsingal]

Originally Posted by Swanand Inamdar

So, again there is no full proof method of using the DSG. Well, thats fine. I guess, to each his own driving style.


Why are we Indians been taken for a ride then? Why cant they admit that and do the same here? Specially when, this isnt a small market for any automotive company by any standards.

Whatever happens to the vehicle, most of the times, mfrs attitude is to pass the buck some how & we Indians, mostly take their excuses on face value. To boot, we have a system that can't care less about customers. As we all know, most of the times, system can be manipulated by corporates & they have resources & legal team to fight, which a normal customer might not have & to top it all, luxury of time is not with the hapless customer. How many of us have listened to the excuse" Sir, this is company policy" or "This is not covered under warranty as per company policy" or something like that? The fact is, we get awed by this "Company" thing, & accept most of the time as "fait Accompli".To hell with this term, a company is also represented by humans & we should challenge this whenever we have to. Companies will keep on doing this till they can get away with these tactics, no matter what the size of the market. Only when, we, the customers, start making life difficult for these corporations indulging in such malpractices, we can hope the things will improve. And that's where forums like our own, TBHP come to picture guiding customers to stand up for their rights . Till then. bear with such treatment :sigh (if not ready to fight).
Never accept this" Company Policy" or "It's your fault" thing if you believe otherwise & take the fight to logical conclusion. You may be amazed what a little persistence can achieve & the difference in results you get.

[V-16]

ANshuman there are no specific driving instructions in the manual. This is a regular automatic transmission dos and donts. Skoda is famous to misguide the customers. Even they dont mention when you buy a 3.6 V6 superb that not using premium fuel will create problems. When you go with your problem to them, they point it out and say u should have used premium fuel.

Originally Posted by SS-Traveller;2620673
@V-16: With 2 DSG failures in your personal experience, have you been told by Skoda at any point of time that the driving style of keeping the shift in 'D' all the time is [B

wrong[/b] (and might have caused the mechatronics failures)?

Well they have not and they dare not else they would have heard from me very strongly.
They did try to get out of the situation with flimsy excuses but i wrote to all the Car magazine editors, with world wide links forums and customer complaints asking them how they could promote such a farce and not even make a mention of it. Some of them even replied that they had problems with their test cars. That worked as much as my letters to the top Skoda management taking them head on. The mention that im a senior member of this forum must have also helped a lot as this forum is not bowed down by any pressures of any car manufacturer unlike most car magazines.

Originally Posted by Hayek

Interesting - they say we don't have to shift to N while stopping for a short while such as at cross roads. Its unclear to me whether that includes the 2-3 minute (or longer) signals that we come across in Bombay, or they are only referring to US style stop signs.

They dont day we must not. It is a may or may not. That should not be the problem of the failure. At the most it can cause wear and tear of the lever components.

Originally Posted by vina

First, reliability is a design parameter, so reliability failure is a design issue.

Second, reliability doesn't only mean mechanical reliability - it means overall reliability including electronics.

Third, AFAIK, mechatronics unit houses the hydraulic controls as well (not just the electronics) so you can't say it isn't a mechanical failure yet,

Fourth, going by your own statement ("pleasure to drive, till it works") - it is an endurance aka reliability issue - still a design problem - but not an initial design problem.

We are being too literal. The very word Mechatronics is evidence of the coming together of Mechanics and Electronics.

Yes the DSG is the most pleasurable auto box is have ever driven.....till it does not fail. If the warranty was extended from 2 to 5 or 10 years, to match international guarantees, id be only buying VW, Audi, Skoda for the sheer pleasure of driving a DSG box.

Here what is failing is not known, is it a mechanical failure or an electronic one as the unit contains both parts. Until that is known, we cant comment. My Laura mechatronic unit was repaired and the failure were mechanical parts but even certain sensors were replaced. Whether the mechanical failure lead to the electronic failure or vice versa, is not known but the mechanic had to import certain O rings and other mechanical parts to mend it and it did work perfectly after that and is still working. The cost was 45k including labour so it was way below what the company charges. Since then the mechanic has shifted back to the UAE i could not find out what exactly were the parts he replaced. But im saying this for the unit. Not the entire Gearbox. The fact that only the unit fails and has to be replaced proves its not a gearbox problem. Thats what i was saying.

A design problem does not have to be initial or immediate. It may crop up at a later stage. This is definitely not an Endurance issue. The link below will explain how this thing crops up whenever it pleases to. Take the issue of my cars. On had clocked 72k odd kms and the other only 20k odd kms. What a gap. Where can one say its an endurance issue. An endurance issue comes from either faulty design or using wrong, cheap or substandard materials which causes the unit to fail around a specific known time or pressue. That im sure they've looked into and replaced if it were the case but the flaw continues so its definitely a design issue. An endurance issue can be compared to the changing of a part due to a known problem, which crops at an approximate known level or around that. The mechatronic failure here is erratic It appears to have a mind of its own so how ca that be an endurance issue. Read the comments of customers on the Golf Gti Forum link i have attached. This link gives a proper explanation of the Mechatronic unit and its functions and failures.

* Volkswagen DSG – 6 Speed Mechatronic Control Unit | my-gti.com

Originally Posted by .anshuman

DSG comes with overheat warning, how many of those who have participated in the poll have seen the warning? Without any data being available, is it fair to blame the design?

Even if it is a MT car, i never use the clutch to hold the car on an incline, i only slip the clutch when it is absolutely necessary.

Yes i have seen this warning in my friend's 06 Laura when we were driving up Mahableshwar Ghat. He was driving on using the S mode when the warning light started blinking. Fortunately by the time we read the manual and figured out what the problem was, we had crossed the Ghat and stopped at Mapro. We cooled of with some snacks and drinks while the car cooled off too. It never happened again and reaching poona we took it straight to the Skoda dealership which mended things. They informed us that the Oil and filters needed to be changed and i guess thats what they did.



* courtesy my-gti.com

[vina]

Originally Posted by anandpadhye

Always, it's a choice between clutch plate and brake pads - what would you prefer to burn?

DSG makes it easier to burn the clutches (or cook the gear oil, or both), Torque Convertor makes it easier to cook the brake pads...he he he.

Whenever I drave an AT (torque convertor or DSG), I shift to "N" whenever I can - to save the gear box (just in case). It's easier to deal with brake pads replacement than any servicing of the AT - IMHO.

Originally Posted by .anshuman

DSG comes with overheat warning, how many of those who have participated in the poll have seen the warning? Without any data being available, is it fair to blame the design?

Even if it is a MT car, i never use the clutch to hold the car on an incline, i only slip the clutch when it is absolutely necessary.

Don't (at least some) AT units come with Hill-Hold kind of function that automatically applies brakes (rather than slipping the clutch) to keep the car from moving backwards when at a complete halt? Slowly moving traffic would of course require clutch slipping but of the same order as MT, so no extraordinary wear should be expected.

Torque converter based designs have pretty low wear and tear but clutch-based designs slipping clutch in such situations should be surprising.

Can DSG owners comment?

Originally Posted by V-16

...

We are being too literal. The very word Mechatronics is evidence of the coming together of Mechanics and Electronics.

...

agreed

Originally Posted by V-16

Here what is failing is not known, is it a mechanical failure or an electronic one as the unit contains both parts. Until that is known, we cant comment. My Laura mechatronic unit was repaired and the failure were mechanical parts but even certain sensors were replaced. Whether the mechanical failure lead to the electronic failure or vice versa, is not known but the mechanic had to import certain O rings and other mechanical parts to mend it and it did work perfectly after that and is still working.
...
Not the entire Gearbox. The fact that only the unit fails and has to be replaced proves its not a gearbox problem. Thats what i was saying.

May be I read it wrong but in the previous post it seemed you were saying it isn't a mechanical failure.

Of course gearbox itself is not a problem, but even within mechatronics unit if O-rings were replaced it is a mechanical problem.

Sensors were replaced is interesting - any idea which ones? By the way, pressure sensors are all electro-mechanical (MEMS are not robust enough yet) so even that might be a mechanical failure - just being pedantic

Originally Posted by V-16

A design problem does not have to be initial or immediate. It may crop up at a later stage. This is definitely not an Endurance issue. The link below will explain how this thing crops up whenever it pleases to. Take the issue of my cars. On had clocked 72k odd kms and the other only 20k odd kms. What a gap. Where can one say its an endurance issue. An endurance issue comes from either faulty design or using wrong, cheap or substandard materials which causes the unit to fail around a specific known time or pressue.

Design problems that crop up with time are reliability/endurance problems. At least that's what I know as a design engineer.

All materials/components - no matter how expensive they are - age. Whether they will still function within their expected lifetime is what reliability engineering is all about.

Also reliability engineering problems are usually framed as "no less than X hours in no mare than Y percent of the parts, under harsher than Z conditions" - with poor engineering also usually a good majority of parts will work very well for long duration. It is just that if Y was supposed to be 99.999% it may become 95% - and suddenly warranty claims eat your entire margin (warranty repair costs are vastly greater than initial manufacturing costs usually). 95% of the customers will never notice anything wrong and even the 5% will see different lifetimes - some more, some less, all less than the expected lifetime.

Originally Posted by V-16

... An endurance issue can be compared to the changing of a part due to a known problem, which crops at an approximate known level or around that. The mechatronic failure here is erratic It appears to have a mind of its own so how ca that be an endurance issue. Read the comments of customers on the Golf Gti Forum link i have attached. This link gives a proper explanation of the Mechatronic unit and its functions and failures.

* Volkswagen DSG – 6 Speed Mechatronic Control Unit | my-gti.com
...

Thanks for the link, though I had already seen it earlier. It does have good information, though I found Direct-Shift Gearbox - Wikipedia, the free encyclopedia and the references therein to have even more information, customer comments are obviously invaluable.

[V-16]

May be I read it wrong but in the previous post it seemed you were saying it isn't a mechanical failure.

Did I? I dont think so.
Im not an engineer or into engineering so i may be given a discount when using technical jargon but most of us are not that technically qualified to understand or relate to the literal definition, therefore, should hopefully get the gist. Maybe you read it wrong. Ill explain, what i meant to say.

1) That it was a mechatronic failure.
2) That since o rings and some other parts along with some sensors had to be replaced, what failed first out of the mechanicals and the electronics is not clear. What lead to the failure of what is not clear.
3) The post never pointed it out to be only a mechanical failure
4) In an earlier post was merely saying that the gearbox (understood as mechanical part) does not fail its the M box that fails.

I have highlighted the concerned sentences for further clarity.

Originally Posted by V-16

Please note the only thing that fails is the Mechatronic and not the gearbox. The unit is changed on the same gearbox and all is hunky dory. Its an external box that feeds info to the gearbox on the changing pattern. A Dsg equipped car is a pleasure to drive, till it works. Gearshifts are extremely smooth and fast, faster than a manual and they adapt to the driving style of the person.

Originally Posted by V-16

Here what is failing is not known, is it a mechanical failure or an electronic one as the unit contains both parts. Until that is known, we cant comment. My Laura mechatronic unit was repaired and the failure were mechanical parts but even certain sensors were replaced. Whether the mechanical failure lead to the electronic failure or vice versa, is not known but the mechanic had to import certain O rings and other mechanical parts to mend it and it did work perfectly after that and is still working. The cost was 45k including labour so it was way below what the company charges. Since then the mechanic has shifted back to the UAE i could not find out what exactly were the parts he replaced. But im saying this for the unit. Not the entire Gearbox. The fact that only the unit fails and has to be replaced proves its not a gearbox problem. Thats what i was saying.

Originally Posted by vina

Don't (at least some) AT units come with Hill-Hold kind of function that automatically applies brakes (rather than slipping the clutch) to keep the car from moving backwards when at a complete halt?

Some cars do have that function, the Captiva and a few others but the Laura does not. My 97 Land Rover Discovery had it but my 96 Pajero did not.

Slowly moving traffic would of course require clutch slipping but of the same order as MT, so no extraordinary wear should be expected.

Torque converter based designs have pretty low wear and tear but clutch-based designs slipping clutch in such situations should be surprising.

Can DSG owners comment?

I have done some hill and slope driving with that when travelling cross city or even when doing stop and go driving within the city and have not found the clutch to slip. Maybe a weak clutch makes this happen. Anyways how many times do we encounter this sort of terrain?

Of course gearbox itself is not a problem, but even within mechatronics unit if O-rings were replaced it is a mechanical problem.

Sensors were replaced is interesting - any idea which ones? By the way, pressure sensors are all electro-mechanical (MEMS are not robust enough yet) so even that might be a mechanical failure - just being pedantic

I would have liked to know. He came back one day after opening the box and pointed out that some small valve looking thing needed to be replaced. And because of that he needed to change a few O rings. He went on to add that out of some 10-12 sensors three had gone and was not clear as to what caused the failure of the other. They are interdependent. SO he ordered the parts and quoted me for the whole job. After delivery i found no problem with the car in anyways and handed hm over his dues. I was so happy that it was fixed at the cost it was, that i forgot to ask him what sensors had gone bad. I remember he had to import another sensor which was not responding again so in all four sensors were replaced and he got the thing working. Amazing i thought, since i know of no other person who has successfully repaired the mechatronic box.

Design problems that crop up with time are reliability/endurance problems. At least that's what I know as a design engineer.

All materials/components - no matter how expensive they are - age. Whether they will still function within their expected lifetime is what reliability engineering is all about.

Exactly.... when things go old they have lived their life. Brake pads have a set life so will you call that an endurance issue also? they do get worn after enduring the stress of 'X' times they are used. If the pads get worn out in say 10k kms instead of 25k kms on an autobox one may blame the driving but if 50 cars of the same company were to undergo the same complaint, it is a flaw. Whether its a design flaw or an endurance flaw remains to be seen. As customers we are not here to analyze the cause of the flaw. Its a flaw...period. It should be fixed.

Also reliability engineering problems are usually framed as "no less than X hours in no mare than Y percent of the parts, under harsher than Z conditions" - with poor engineering also usually a good majority of parts will work very well for long duration. It is just that if Y was supposed to be 99.999% it may become 95% - and suddenly warranty claims eat your entire margin (warranty repair costs are vastly greater than initial manufacturing costs usually). 95% of the customers will never notice anything wrong and even the 5% will see different lifetimes - some more, some less, all less than the expected lifetime.

Sorry but this does not work here. There is no life or duty span of a mechatronic box specified anywhere. there is no precedence where any inference may be derived. If there is, what is it and on what is the information regarding this based on.

The mechatronic box is not available outside the company, at least in India and is not very commonly available abroad too.

The question is;

How many hours/months/years/kms do you think the mechatronic box should be good for?

50k kms? 75k kms? 100k kms? My question again is why only this much? What are the parameters set for the M box? On what are these parameters based? There is no time frame or endurance formula e for these things. Lastly why should i care as a customer. If the company does not have an answer to these things they will not be able to convince the customer today that it is because of his wrong doing.

Im sure you have no answer too!!

I feel it should run as much as the gear box does at least or should be repairable. We have seen it is so im sure Skoda want to make money out of selling new ones by making it difficult to repair.

[Sutripta]

And the clutch <-> mechatronic saga continues unabated!

Originally Posted by gthang

Coming back to topic, given that the previously mentioned DSG caution is not applicable for regular automatics, would you say that driving style for both can be the same?

Cheers

So don't use the DSG for hill holding!
But then again, though not mentioned, it is also not advisable in normal ATs.

This thread is on DSG failures. Where is the link between driving style and failure. I'm not even getting into should the driving style be changed. Which is why I'm interested in seeing whether they officially mention it anywhere, rather than in a whispering campaign.

Regards
Sutripta