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Old 4th March 2020, 12:54   #121
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by vDragon3 View Post
This is what should have been done by KIA when you had initially reported the issue! Software update stories just seem a reason not to replace a faulty part under warranty.
Unless and until there are specific error codes , it is very difficult to pin point the issue , even if you physically inspect. However they have lots of debug info from transmission using which they can find the issue ( may be some special devices are required to extract that info but not sure ) This is what I was told when I had issues with my old ecosport DCT. Irrespective of all these things, the first thing ( since it is easy and it may rectify issues often ) they do is update the software before doing ( or even looking at ) any hardware components. In my ecosport also they updated the software twice before they looked deep at hardware issues.
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Old 4th March 2020, 20:24   #122
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by ecenandu View Post
As the Kalman filter, using different sensor values to deduce another measurement.
Sure, lots of values are derived/ estimated. Except for trivialities, requires (deep) knowledge of the system, the ability to model accurately.
Question still remains of what sensors. Esp valves (and operating currents), as has been mentioned.

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Old 5th March 2020, 00:58   #123
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Sutripta View Post
So a derived value. Derived from what?

Now the enlightenment on valves and currents please.

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Sutripta
Quote:
Originally Posted by ecenandu View Post
As the Kalman filter, using different sensor values to deduce another measurement.

What he is referring to here is a simple map lookup, for example, a single-dimensional map.
Quote:
Originally Posted by Sutripta View Post
Sure, lots of values are derived/ estimated. Except for trivialities, requires (deep) knowledge of the system, the ability to model accurately.
Question still remains of what sensors. Esp valves (and operating currents), as has been mentioned.

Regards
Sutripta

In a vehicle brake system ( ABS systems), between the master cylinder and wheel cylinder, there will be a minimum of two valves (Inlet valve and outlet valve). A combination of opening of these valves will ensure the pressure is increasing or decreasing or pressure is held constant in the wheel cylinder
For e.g, when the inlet valve is opened fully and the outlet valve is closed, pressure increases in Wheel cylinder and brakes are applied
When the inlet valve and outlet valve is closed, then pressure is maintained and the brakes will maintain the current pressure level.
When the inlet valve and outlet valve are partially open, say inlet @ 40% and outlet @ 60%, most probably , the pressure in wheel cylinder is reduced but it is reducing at a controlled rate.
These valves are actuated by solenoid and the currents that drive the solenoid are estimated by the brake controller based on sensors such as wheel speed , deceleration rate .

So in the case of a mapped sensor, a reverse model is created to estimate the wheel cylinder pressure based on valve currents. As mentioned by ecenandu, the simplest method of the reverse model is a one-dimensional table whereas the Kalman filter or virtual sensor are sophisticated implementations.

Note: This does not apply for non-abs where brakes are in an open-loop configuration.
Note: Somehow, I feel it is getting off-topic and hijacking the original objective of the thread.

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Originally Posted by audioholic View Post
This type of direct logic will be the annoying part when we are trying to park the car by moving small distances at a time and stopping.....
True. This is where the expertise of the manufacturer comes in play in deciding like how much should be clutch engagement,rate of engagement, what speed is considered as stopped condition etc and will determine how jerky or smooth would be the vehicle at crawling speeds

Last edited by Doo_Dev : 5th March 2020 at 01:17.
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Old 5th March 2020, 12:53   #124
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Default Re: Serious gearbox issue in my Kia Seltos DCT

Finally! Well done buddy! Perseverance pays off. Have they assigned an ETA? I really hope this resolves the problem once and for all. You might want to check with your local KIA service centre if they have the technical knowhow to replace the part correctly. Reason being - its a new company and this MAY NOT have been part of the training for the staff at the service centre.
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Old 5th March 2020, 20:42   #125
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Doo_Dev View Post
In a vehicle brake system ( ABS systems), between the master cylinder and wheel cylinder, there will be a minimum of two valves (Inlet valve and outlet valve). A combination of opening of these valves will ensure the pressure is increasing or decreasing or pressure is held constant in the wheel cylinder
...
Discussing ABS would certainly be OT for this thread, though there is lots to discuss. But for starters in the context of this thread - crawling in stop go traffic - does the ABS come into play at all?

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Sutripta
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Old 5th March 2020, 22:40   #126
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Sutripta View Post
For the purposes of this thread what is 'incomplete' pressing of the brake pedal? How does the system know it.

Regards
Sutripta
If the car has anti-lock braking system (ABS), there is a computer reading the wheel speed and controlling the brakes.

So if a brake is applied, which is way less than the required amount of force, immediately computer is notified and message is sent to the console and there we can see it.

Pragmatically : Relative speed of the vehicle, obstacle distance and brake force applied = +ve value, you have applied brake whose force is way beyond normal limit (which might give a jerk). -ve value, you have applied brake whose force is way less than normal limit (which might give incomplete/something like that in the console).
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Old 6th March 2020, 18:26   #127
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Sutripta View Post
Discussing ABS would certainly be OT for this thread, though there is lots to discuss. But for starters in the context of this thread - crawling in stop go traffic - does the ABS come into play at all?
Excellent question - I could be wrong, but I don't think ABS would come into play in stop go traffic. Exceptions may always be there, but you hardly lock up your brakes in regular traffic.
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Old 6th March 2020, 19:55   #128
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by vk007 View Post
Excellent question - I could be wrong, but I don't think ABS would come into play in stop go traffic. Exceptions may always be there, but you hardly lock up your brakes in regular traffic.
Typically, ABS activates beyond ~20 km/hr UNLESS you're on a gravel surface, and the ABS sensors realize that the wheels are locking up even at that slow speed.
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Old 8th March 2020, 21:29   #129
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by Sutripta View Post
crawling in stop go traffic - does the ABS come into play at all?
The ABS/ESP module will be active and will be doing its calculations as usual in all conditions. It just doesnt intervene with the accelerator or brakes.
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Old 8th March 2020, 23:02   #130
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Default Re: Serious gearbox issue in my Kia Seltos DCT

^^^
Of course. But will any of the actuators be activated?

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Old 10th March 2020, 22:00   #131
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Default Re: Serious gearbox issue in my Kia Seltos DCT

At last, got the car back after almost 12 days.
They say that they have replaced the gear actuator unit. No issues on a longish test drive that I took. Gearshifts are seamless now.
I did not get any documentation either by mail or on paper. I have requested them to send a summary by mail.
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Old 11th March 2020, 09:35   #132
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Default Re: Serious gearbox issue in my Kia Seltos DCT

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Originally Posted by sandygordon View Post
At last, got the car back after almost 12 days.
They say that they have replaced the gear actuator unit. No issues on a longish test drive that I took. Gearshifts are seamless now.
I did not get any documentation either by mail or on paper. I have requested them to send a summary by mail.
Do insist on documentation. Thank god the gearshifts are seamless now. And keep us posted please.
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Old 15th March 2020, 21:24   #133
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Default Re: Serious gearbox issue in my Kia Seltos DCT

Glad to know you are back at your wheels.Getting the whole ordeal documented certainly needs to be done.Though they initially goofed up with the resolution ( by merely updating the software ) , it augurs well that Kia has taken time to study the issue closely and came out with the diagnosis and fixed it.

Having said that , their lackluster response (in diagnosing the issue and taking cover under the perennial quick fix of ' updating software ' ) initially surprised me as this issue had the potential to snowball into something big for Kia to contain.We as customers would like to have promising assurances coming from them thick and fast than knee jerk reactions ,especially from a new entrant like Kia.It's such a good company whom we car lovers don't want to lose in the long run and they are the one who infused so much of life to an industry that has been on a nose dive.

Have you spoken to the dealer guys about giving gear box warranty beyond the default manufacturer warranty? I mean extend it a couple of years
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Old 25th May 2020, 10:09   #134
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Default Re: Serious gearbox issue in my Kia Seltos DCT

UPDATE
3000 km post gear actuator replacement for my car
No issues yet. Gear shifts are seamless. No skipping of gears even in scenarios where I had issues. Hope this is limited to just one car.
Hope this is settled for ever. Fingers crossed.
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Old 28th May 2020, 14:20   #135
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Default Re: Serious gearbox issue in my Kia Seltos DCT

hi Sandy, all,

I had faced this exact same issue in December twice on a single day but never faced it later on any of my drives. Exact same scenario(gear stuck in D2)

I had raised this issue during my first servicing in december but they couldn't reproduce it.

Now my car has gone today for second servicing and I happen to come across this post. I have asked the Pune KIA service manager to look into it but they are clueless. They are as usual speaking about software update and stuff. I have told them explicitly that it's a gear actuator assembly issue.

They said they will revert after checking.

Regards, Nitin

Last edited by nitinhegde : 28th May 2020 at 14:22.
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