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Old 4th January 2020, 19:09   #31
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Default Re: DCT Gearbox issue: Follow up from Kia

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Originally Posted by sandygordon View Post
Hope this is a software glitch. Fingers crossed
More knowledgeable bhpans may correct me if I am wrong, shouldn't the problem occur in all vehicles and at all times if it is indeed a software problem?

Not being able to shift gears even in manual mode is a big concern as per my opinion.

I am sympathetic towards the OP and even the service centre guys, not much can be done other than be nice and be helpful as much as one can, hope for the best.
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Old 4th January 2020, 19:26   #32
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Quote:
Originally Posted by gauravanekar View Post
More knowledgeable bhpans may correct me if I am wrong, shouldn't the problem occur in all vehicles and at all times if it is indeed a software problem?

Not being able to shift gears even in manual mode is a big concern as per my opinion.

I am sympathetic towards the OP and even the service centre guys, not much can be done other than be nice and be helpful as much as one can, hope for the best.
Not necessarily, software is just instructions written to behave in a particular manner under a set of given conditions. If an unforeseen condition occurs it causes a fault also known as a bug. It is quite possible for some cars to never encounter that condition while some other may.

The fix would be to identify that unforeseen condition and fix the software so it knows what to do.

Having said that, the bug/glitch should not have been there in the first place if enough testing would have done. However like everything nowadays nobody has time to do that and they push out half baked products all the time. Customers become Guinea pigs and they actually do they testing later.
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Old 4th January 2020, 19:52   #33
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Default Re: Serious gearbox issue in my Kia Seltos DCT

If I were a manufacturer, I'll focus efforts to aggressively develop a standard 8-speed torque converter for high power and low power engines.

The torque converter is the most reliable of any automatic transmission till date, and has some great side-effects as well like incline holding ability without a need to program a hill hold.

The gear change ratios must be highly aggressive, 0-5 1st gear, 5-15 2nd gear, 15-30 3rd gear, 5th gear by 60 and then the final 3 gears can spread the torque all the way into 120 (legal highest speed in India). I want massive bottom end torque which the idiotbox TC doesn't have and which is the most redeeming factor in DCT.

DCT is simply too imperfect at this stage it seems heavily reliant on software, to me software (anything other that hard coded ECU) when it comes to driving is best avoided. Every software on earth is imperfect and all the coders know it, it comes with more holes than a block of cheese. When the tuning sings with the programming, the result is magic but when the holes in the variables show, its horrendous.

Hyundai in general, the automatic gearbox tuning is amongst the worst I've seen, the initial pickup is criminally low. Venue DCT was a slug in initial rolling, a Mini would've hit the ton mark by that time and accerator pedal input. Kia should be kind of similar or is it more aggressive? The engines support good torque and HP, but the gearbox sucks away 90% of the performance.

Last edited by dark.knight : 4th January 2020 at 19:55.
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Old 4th January 2020, 19:56   #34
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Default Re: Dct Issue Again

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Originally Posted by d3mon View Post
There's a recall in Korea for the exact problem, which is that "Some DCT models are suffering an issue that only drives with 2nd, 4th, 6th gear. 1st, 3rd, 5th, 7th gears are not working."

The actual recall notice is in Korean, but some quick Google Translation-fu reveals that the reason for the failure is mechanical.

"Burr removal in 387 speed hub manufacturing process is insufficient"

https://thekoreancarblog.com/2019/10...n-south-korea/

It's unfortunate that they have not been able to iron out (pun intended) this issue before the India launch.

Please insist on a full gearbox replacement as Kia know it's a manufacturing defect, and that's the process they are following in Korea.
The OP should contact the National Consumer Forum. https://play.google.com/store/apps/d...mtcdev02.udaan


With the newer more stringent laws, it is bound to scare Kia into taking appropriate action. I think just talking to Kia will not result in quick, satisfactory action.

The information quoted should help immensely.
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Old 4th January 2020, 22:32   #35
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Default Re: Serious gearbox issue in my Kia Seltos DCT

I am happy to know that there is a fix available atleast on temporary basis. Also it seems the escalation is on the right track. Typically DCTs have a dedicated TCU for its own mechatronic operation. I am not sure whether my thoughts make sense. Anyhow, there is a chance that the functional safety parameters overriding the operational code to save the transmission from getting damaged. To my knowledge, a functional safety code is embedded as well . An improper heat dissipation for clutch 1 could be a reason. If its wet clutch, oil flow may be hindering. No matter what, Its definitely a brain stormer for Kia HQ. As DCT is a maturing technology, so is its validation methods. But some customers become scapegoats.
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Old 5th January 2020, 11:11   #36
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Default Re: Serious gearbox issue in my Kia Seltos DCT

I knew we would soon get a Hyundai/KIA DCT woes thread on here, but honestly did not expect seeing one so soon.

On the positive side, unlike VAG and Ford, KIA was quick to acknowledge there was a problem and looks like they are working to fix it. Being a DCT heat will be an issue in our traffic conditions and this being a dry clutch unit we will have to wait and see how this will fare in our harsh (low speed, stop and go, tropical) conditions in the long term.

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Originally Posted by sandygordon View Post
He agreed that this issue had cropped up in many centers all over India and most of them has no new issues after the patch update.
If this issue is so common then I wonder why KIA didn't pick it up during their extensive road trials in India before launch.
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Old 5th January 2020, 12:10   #37
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Sankar View Post
If this issue is so common then I wonder why KIA didn't pick it up during their extensive road trials in India before launch.
One possible reason - the testing is mainly done outside the cities. Unless it's a car like the Harrier in LR guise, I dont think the OEM's will risk driving the cars in city conditions.
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Old 5th January 2020, 12:34   #38
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by condor View Post
One possible reason - the testing is mainly done outside the cities. Unless it's a car like the Harrier in LR guise, I dont think the OEM's will risk driving the cars in city conditions.
All the incidents happened after 20-30 minute drive through congested Kerala roads with gradients and curves. Involved lot of 2-3-4-3-2 shifts.
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Old 5th January 2020, 12:41   #39
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Default Re: Serious gearbox issue in my Kia Seltos DCT

Quote:
Originally Posted by Sankar View Post
If this issue is so common then I wonder why KIA didn't pick it up during their extensive road trials in India before launch.
Quote:
Originally Posted by condor View Post
One possible reason - the testing is mainly done outside the cities. Unless it's a car like the Harrier in LR guise, I dont think the OEM's will risk driving the cars in city conditions.
Rarely do we see road trials being done "consciously" in bumper to bumper traffic/ city crawling traffic.

That possibly explains why we don't witness the auto-trannies in action while trials.

My office route is on the Pune - Bangalore highway + some on city roads, and almost all the test mules that I see around, are zipping around like crazy - mostly on the highway asphalt.

Last edited by suhaas307 : 28th February 2020 at 11:07. Reason: Spacing
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Old 5th January 2020, 15:25   #40
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by sandygordon View Post
All the incidents happened after 20-30 minute drive through congested Kerala roads with gradients and curves. Involved lot of 2-3-4-3-2 shifts.
Someone on the FB group mentioned this and I have to agree with his explanation.

It seems the clutch pack controlling the odd gears is heating up in your car and to prevent further damage, the TCU is avoiding those gears altogether. Another reason might be a faulty sensor which isn't giving the TCU correct inputs and is fooling it into thinking the clutch pack for the odd gears has an issue.

Please get it checked at the earliest. I am more worried about the car starting off in 2nd gear rather than first. This will put unnecessary strain on the functioning clutch pack and cause it to wear out prematurely too.
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Old 5th January 2020, 22:49   #41
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by vishy76 View Post
It seems the clutch pack controlling the odd gears is heating up in your car and to prevent further damage
This explanation is not so convincing. There is just one "clutch pack" which contains both the set of clutch discs for either gear sets. These are not two physical separate clutch assemblies and lie concentric to each other on the same shaft. So it can't be that only one clutch can overheat. In the VW DSG, the clutch discs are coaxial and one set is it smaller Dia, works within the center of the other clutch disc which surrounds it. However in the KIA the clutch discs are similar in size and is stacked parallel to each other within the same clutch cover. So it's practically not possible for only one set of clutch discs to heat up.

Coming to the actual issue, the KIA DCT construction for the 7DCT is pretty wierd. In comparison, the VW mechatronics has separate solenoids for odd and even gears. They work independently to select gears. In the KIA, there is a single shift selector mechanism which alternates duty between the odd and even gear selection. This is pretty complex in construction as well as control. If the mechanism/software to do this role switching activity fails, the selector can only switch between one set of gears and is like having only half of its functionality. This is understood as a fault and hence instead of breaking down completely, the transmission shifts between whatever gears are available. In this case it was the even gear set. If this is a software glitch which I bet on, then it will be solved. If it repeats, then it could be a mechanical issue as well.
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Old 6th January 2020, 04:13   #42
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Default Re: DCT Gearbox issue: Follow up from Kia

Quote:
Originally Posted by gauravanekar View Post
shouldn't the problem occur in all vehicles and at all times if it is indeed a software problem?
Even if it is hardware problem, software can fix it if possible. Software can avoid the system getting into the error state if its clear what sequence of actions lead to the error state. One more strategy could be software can detect the error state and recover from it.
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Old 6th January 2020, 06:58   #43
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Default Re: Serious gearbox issue in my Kia Seltos DCT

A brand-new car with a failed transmission is a LEMON! When will people understand this?! The buyer deserves compensation.

Dual-clutch transmissions are complex and even a company like Ford burnt their fingers with it. Of course, they recalled vehicles abroad but not in India. Subaru gets so much flak for the CVT gearbox in the WRX and I agree that it's far behind the superb VAG DSG but I can understand why though. Making a reliable dual-clutch transmission is damn tough.

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Originally Posted by kiku007 View Post

However, the below part is disappointing.

Niggle: Criticize someone about small details or give too much attention to details. To worry someone slightly, usually for a long time.

A rattling parcel tray can possibly be classified under niggles. Personally, I would get it fixed ASAP.

But how can things like air-con issues and leaking coolant reservoir be treated as niggles? I can understand the mindset of the general public who rush to buy the newest toy in town without waiting to confirm the product's reliability. And there's the other extreme of the odd customer who resorts to stunts using donkeys and what not when a brand new car breaks down.

Shouldn't TBHP treat these things more seriously? The affected cars would be classified as lemons in developed markets and KIA knows that.

It's this forgiving habit that has resulted in the Innova having its 'niggles' thread and Tata delivering the Harrier which apparently is half-baked.

Reliability and build quality should not be ignored in the hype surrounding features and gizmos.

Last edited by kiku007 : 6th January 2020 at 07:01.
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Old 6th January 2020, 07:52   #44
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Default Re: Serious gearbox issue in my Kia Seltos DCT

The more my heart pulls towards a DCT gear box my brain says a firm No! I think the tech is not for the sort of grid locks we see here in India. It's basically a flawed tech that's been unleashed and just improved and not as reliable as the CVT or good old torque converter.
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Old 6th January 2020, 09:20   #45
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by audioholic View Post
This explanation is not so convincing. There is just one "clutch pack" ...
it could be a mechanical issue as well.
This is the most logical explanation any Team Bhpian has put on this thread till now. I dont know how many understood the intricacies of the explaination but @audioholic Hats off to your logical explanation.

Issues which can cause Odd or Even Gears not to shift:

1) Faulty Software code for Transmission Control Unit (TCU)

2) Faulty sensors

Clutch overheating - faulty sensor error. Oil cooling has failed or is it the sensor is giving a wrong information.

Lets say a sensor has to operate at 60 degree°C but not all sensors will operate exactly at 60 degrees. Some will operate at lower or higher temperatures. Some sensors sense position again here there can be calibration error.

3) Faulty clutch - Can be because of a mechanical issue or lack of oil supply etc. Or a Clutch actuator solenoid issue

4) Faulty solenoid actuator for shift assembly

5) Faulty shifting actuator assembly, some mechanical issue which avoids shifting like a burr

6) Synchroniser assembly issue - Manufacturing defect

Last edited by suhaas307 : 28th February 2020 at 11:09. Reason: More points added / spacing
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