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-   -   DSG Mechatronics Failures: Are we driving them wrongly? (https://www.team-bhp.com/forum/technical-stuff/112863-dsg-mechatronics-failures-we-driving-them-wrongly-9.html)

I am given to understand that the DSG does have an oil cooler. Someone please confirm on this.

Yes. An external oil cooler does exist.

For good breakdown of DSG, please read:

DSG

Cheers.

Wow

how did you find this?

From first looks, (I haven't gone into details) this "mechatronics unit" is more mechanical than electronic - sure the sensing part is electronic sensors, but most of the "brains" part are not even sitting in this.

Electronics Sensors/actuators usually are fragile parts and I'll not be surprised if those are failing in droves over use.

:thumbs upAbsolutely correct and exactly what i have been trying to say but you my friend are more eloquent:D




May be right but then why were the previous Laura DSG's failing too? My Laura was a 2006 and the Superb a 2009. Surely the first batch of DSGs would have not been continuing for 3 years and counting. Maybe Skoda are feeding this to people who are asking questions but not satisfied with their answer.

Then again the M boxes are not manufactured here and are manufactured in some developed European country whereas the power failure thing happens only in Inda and around its neighbors.

So the Mechatronic is an over engineered Valve Body!! Logic says its right and thats what i believe too but the technicians at Skoda said its not a valve body, anyways ive stopped believing them a long time ago.

The question is why didnt Skoda change these faulty units afetr getting complaints?
Why didnt Skoda recall any of their cars for this complaint?
Why did Skoda continue to use the faulty part (assuming it was an assembly line fault due to power failure or whatever) even after knowing that it was faulty and even after that, on receiving several complaints thereafter.

The conventional torque converter automatic transmission is used in automatic mode always, except for parking and reversing. DSG is a brilliant concept, but recently (relatively) introduced. Till a knowledge base is built up, neither we the drivers not the designers really understand how it will behave under varying driving conditions. The DSG is failing in alarmingly short time, so there must be some thing wrong some where, and that is the discussion topic. Had its failure been predictable it would have solved a lot of heartburn. But like random software failure (under specific conditions), DSG failure has yet not been identified with any thing.

What we are discussing here is whether we are driving DSG correctly or not. The manual may omit some things, and (god forbid) gloss over other things, but says nothing about do's and dont's of using it in B2B traffic or on changing to neutral for long stops. In my opinion they are clue less as we are. Regarding keeping the DSG in D while stopping - they have not specified how long, which is what is being discussed. I guess they did not envisage stoppage time of 3-5 minutes every 10 minutes for a 20km ride.

Thanks for the link. Really useful.

However, a (admittedly cursory) reading reinforces (in my mind) that keeping the vehicle in D at stops is NOT the cause of failures.

The DSG is supposed to protect itself from higher temperatures. Quite apart from the fact that normal driving should not result in abnormal internal conditions.

Now would really like a reference to official VW statement pointing out driving habits/ keeping transmission in D as source of failure.

Regards
Sutripta

Simplistically, a DSG is still a auto box and whoever designed it should have made sure that it works like one from the user's point of view irrespective of the internal details.

Good Googling :D

If you see in side of the page which I linked, you can also find the official VW Technician's "Study Guide" on the DSG. Even in that, there is no mention of driving technique. The only warning given is for temperature.

From the "Transmission Digest" article posted, one of the main concerns they had was that the transmission was not "rebuild-able" due to the hardware/electronics integration. This is what failed DSG owners are frustrated about. That they have to be replaced at huge costs.

All the articles you read, one thing which is clearly mentioned is that 150C is the temp limit for many components. It has overheat protection, but only for a certain number of sensors. Their limit is exhibited by warnings and temporary shutdowns. But there are other sensors and CPU components whose failure means complete shutdown of the system, "without warning". Now, since the "unwarned" sensor failure and CPU flash memory corruption is random, I'm guessing VW have not been able to pinpoint the failure cause, and hence dont know what to recall. Purely my speculation.

So, the only culprit which is within our control is temperature, and as we know, extended periods of stall and creep generates heat. Hence the suggestion to shift to N. I fail to understand why such a simple suggestion was turned into an insult, or attack of one's driving style.

Happy New Year to all.

Cheers.

You hit the nail o the head. Personally im still not convinced that it ought to be driven in a way which is slightly different or involved the use of a certain skill. Its not mentioned and if it were,i wouldnt have bought two of these cars, which incidentally i love driving, but am never buying a Skoda with a DSG....if i can help it:D

There is no reference like that Sutripta, ive not come across it and i dont think will ever. I do not agree to this explanation of jumping between the N and D positions of the gear selector. In fact by doing so there is more stress on related parts. I think its the case of over indulgence in a topic and and getting carried away by adding our own two bits, not as suggestions but as a fact, which is what takes a topic off track.

As you have aptly put it, if a company makes a certain product, it should make it good enough to withstand the whatever abuse it foresees or what abuse the preceeding product must bear. This is an improvement so how does an improvement actually become worse than its predecessor? If that is only the temp the Mechatronic can withstand, I really wonder what would happen in hot pockets of Africa and the Gulf.

Again PLEASE NOTE, the DSG gear box is not failing, its also not being replaced, its only a component, i.e. the M box which is the cause of the problems and which is being replaced!!

I don't recollect coming across the 150C figure anywhere. Design temp range seems to be 135. With corrective action at 138 and 145C. Not that it matters to the user.
It has three temperature sensors. Which crosscheck each other for redundancy.

After statements like

shows that temperature was given very careful consideration. Thus blaming temperature now means somewhere in design or manufacturing VW have balled up. Also, to the user it does not matter whether internal components can withstand 150C or 1500C.

Which should be taken care of. Not the users responsibility, as long as he is not abusing the car.


Because the tone of the previous posts was nowhere near as reasonable! (I'm feeling that now you are coming round to our point of view!)
For any person who has suffered at the hands of Skoda, your posts were the perfect red rag to the bull. Seemed to be deliberate flame bait.


I also don't think there will EVER be an official statement like that. Which is why these whispering campaigns really upset me.

Those who have not had a run in with Skoda will not understand the mindset of those who have. I could at least take a more philosophical attitude in that the vehicle was not mine. (And no, it was not DSG based!) And I was livid.

Disclaimer: I've never owned a VW product.

A happy new year to all.

Regards
Sutripta

Coming to the temparature sensors. The sensors may activate action at a given cut off point. But that does not mean that the temperature will stop rising.

Some case where the temperature rises
- You may noticed that the coolant temperature rises once the vehicle is switched off.
- You are supposed to run the turbo for some time after the engine is switched off to cool it.

Thus even through the sensors in DSG act, they may not be successful in arresting temperature rise. Electronics fails catastrophically after the threshold is reached, no case of soft failure here, and as the electronics is embedded in the unit; for the sake of compactness; the whole unit fails.

So in my opinion embedding the electronics; without adequate provision for cooling them in case of any malfunction; is a design flaw. May be the designers never faced these conditions in Europe, but then they are selling it globally and should be aware of it by now, and gracefully acknowledge the problems faced by the DSG users.

Au contraire, Mon ami!

Please see post #63, if any different from my above post. Please advise how my tone was unreasonable.

If anything, I feel it is only now, after 2 pages of assault with reading between my lines, and false accusations like:

(I wish he would have substantiated that with a quote of mine), that you are even willing to discuss the matter of temperature increase (150c was an approx. figure). I have been told that I am persistent, and I am starting to believe it.


If personal opinion of Skoda is one of the basis of this discussion, I fail to understand it being in the Technical section. I doubt any Skoda employee, technician, or official is going to come on this thread and set things straight. So, isnt the idea to discuss possible scenarios, and suggestions to future DSG failure inflicted visitors to the forum?

I hear a lot of "It is supposed" to handle it remarks. If that was the case, how many car manufacturers, some Indian ones in particular would have survived?

Can anyone, with any amount of authority, say what percentage of DSG failures was directly as a result of poor driving? It's anybody's guess what that figure is, but not for Skoda. They should have records. Now, if the people who actually know the figures, tell you to drive different, without knowing that you are a Senior member on an internet forum, are they to blame?

I still state the same, to prevent premature failure of DSG, in addition to praying to your preferred God, it is also a good idea to shift to N during extended periods of stall and creep.

Do you feel the same way when it gives you better fuel economy and better driving response compared to conventional automatic?

Cheers.

@V-16, I certainly empathise with you. Having 2 DSG failures in short order is not fun, and certainly represents the luck of the draw rather than anything else ( for at least the reason that your Laura broke after several years and loads of miles, else you would presumably have not bought the Superb). DSG failure represents a nightmare scenario for any Skoda owner.

But I don't see how moving to N is anything but a no regrets move. The entire purpose of Neutral ( as opposed to Park) in any transmission is to reduce stress on the system while idling for more than a brief period. Based on just how the Superb, at least, strains on the brakes when you hold it in D, it seems intuitive that moving to N will reduce wear and tear (at least on the brakes if not on the transmission or it's components). Further, I don't see how shifting to N introduces any kind of "additional stress on related parts". Would appreciate an explanation of how that happens.


Technically, you are right. But we all know that DSG boxes fail more frequently than they should, not just in India, but also in Europe. So there is no point hoping for something that VAG clearly has not achieved. Further, traffic conditions + heat in India (or at least in Bombay ) represent in my view the most stressful driving conditions possible. There is no other city I know where 15 kmph is a decent average speed and average speeds frequently drop to less than walking speed. Combine that with 35 degree plus temperatures except for a brief spell from late December to mid Feb, and you have a recipe for disaster for any system with cooling troubles.

There in lies the rub. If every manufactured product lived up to its expectation; especially in the initial manufacturing run; life for all consumers would have been easier.

Many products released in consumer market have a whole lot of glitches and niggles. Efficient and conscientious companies, attend to the problem, and in a reasonable time the released product (V2?), works as desired. Unfortunately, many companies either do not learn or simply do not care. This is evident from the number of niggles found on newly released Indian cars, and are taken care of at a leisurely pace.

There fore my contention is that VW may have an inkling of the reason for DSG failure, but simply refuses to share it with public, as that would result in heavy financial loss - due to legal action and recall. In Europe and US they have extended the warranty and replaced all the faulty units. Let us work for similar action in India.

Lastly we have been constantly arguing on, whether driving technique with DSG should be same as the driving technique with the normal torque converter automatic transmission or different. DSG is not normal automatic transmission, but a new concept with different technology, hence I would not expect it to behave similar to the torque converter.

The brilliant performance of the DSG is amongst others dependent on electronic controls. Note that the torque converter automatic has no electronics inside it hence it can withstand harsher environment. Electronics fails catastrophically at high temperatures, and just a couple of degrees centigrade makes all the difference. That is why it is the Mechatronic unit which is failing and not the gear box, which is a conventional mechanical unit.

I would never have comprehended till pointed out by you that the tone of your penultimate post was same as that of your other posts. Guess it is remedial English classes for me now!
So I guess other people can best answer your query.


There is more to it than just technical discussions. My very first post on this thread (I think #2), and subsequent posts should have made clear my focus.
And of course everything here is a personal opinion. Resting either on facts or fantasy!


I doubt that too.
But why do you think Skoda will not participate?

Somehow I feel (personal opinion only) neither will help!
Disclaimer: I'm agnostic.

Regards
Sutripta