Pinkawa

Hello I wanted to give an update.
the shift rod position Sensor from T-Design9 was installed.
the calibration with PIWIS aborts at like 96%.
Failure code P1872 - "Data record for hydraulics calibration is invalid".
I have some contacts do Germany and will check but I have the suspicion that the sensor delivers values outside of the tables in the control unit.

Any input is much appreciated.

Would also be interested in T-Design9 quality control system.
I hope they stand behind their product in case this is not working out for me.
For the record : My original fault code was P1731.

TIA

t-design

Never seen that error before... PDK is a complex thing, with many components, quick search shows that the error is related to PDK control unit software, particularly in hydraulics area, see full document attached. From this document - it's pretty clear it's not related to distance sensor/shift rods in any way... here's the quote:



Here's also some link to real world case, again looks like software kind of error, those guys were able to overcome by software reinstall
https://rennlist.com/forums/997-foru...ml#post6893914

May be PIWIS software is also involved somehow, and not up to date - doesn't have correct data record for the hydraulics calibration ?

Distance sensor has plenty of error codes related to it, but 1872 is not one of them. You indicated you had 1731 error when ordering sensor... Can we assume that error is not there anymore?

We do stand behind our product, but can't help with unrelated PDK issues

Kuro Neko

Not being a PDK expert, but with experience in diagnosing electric and electronic issues, I would suggest the following:

• Ensure PIWIS is up-to-date.
• Confirm full set of initial error codes - did they include those present now? Or, are there new codes?
• Confirm original error with shift rod sensor has gone?
• Ensure all connectors and similar are in their normal state and functioning, I think there are a number of basic DC checks available for a lot of PDK elements?
• Clear codes in order of their presentation - I assume Porsche's flow has logic, so follow it. In this case, work through the error codes being presented sequentially.

I know this is self-evident, but I've seen countless professionals approach complex issues with the shotgun approach, and this often results in getting tied in knots.
If at all possible too, try to effect one change at time, so that it can either be built on or backed out.

Good luck!

PV997

I mentioned this before but I'll state it again. The PDK transmission control unit (TCU - inside the car) stores adaptation values that are matched to the PDK. These adaptation values are characteristics that are developed over time using an algorithm that matches the PDK performance to the driving style and PDK wear. If you run the Vehicle Analysis Log you can see them, there are literally thousands of values unique to your PDK. I'm not certain but I don't think these adaptation values are completely cleared/updated by a calibration as they have different purposes. (Edit: see amet's comment below about two different types of calibrations, it's relevant.)

There are many reports of shops claiming the need to replace the TCU ($800) after a PDK replacement in order to get things to work. When they do this they are switching to a TCU with a clean slate (no stored adaptation values) so the synchronization, calibration, and adaptation goes smoothly. Do some searching around and you'll find multiple reports of this.

I do not think a new TCU is needed but I do think it may be required to clear the adaptation values and reinitialize the TCU. The reason for this is that when the transmission was malfunctioning the TCU may have developed unusual adaption values in an attempt to cope with the problem. Now that the problem is fixed the adaptation values are so out of whack that the TCU senses things are beyond the normal range and throws an error.

T-design is almost certainly right when they state this is not caused by their unit. Your P1731 codes are gone, this is a software fault as the document T-design posted shows. The PDK itself has no software whatsoever, it's simply a dumb box with solenoids and sensors. Software errors are in the TCU. Search around in your PIWIS for initializing the TCU to get it back to a clean slate. Your comment, "I have some contacts do Germany and will check but I have the suspicion that the sensor delivers values outside of the tables in the control unit." (deleted)

Edit: After thinking about it you might be right in that the sensor is supplying values outside the table range, but the problem is not with the T-design unit. The problem is with the tables in your TCU. I've edited out the sentences I had above as I probably read more into your comment than I should have.

BTW, I'm an electrical engineer that knows a lot about the PDK but in no way am I qualified to tell you how to use your PIWIS on your car. You can do some real damage if you are not careful so please do your research and tread lightly. Most of the "software faults" in the Porsche T-shooting document state that the fix is to replace the TCU. If it were my car I would try TCU initializations with the PIWIS before replacing it. That being said, a new TCU is not very expensive in the big scheme of things.

Good luck and please provide updates.

amet

Piwis has the report and the reason why calibration failed, can you post more from there please

distance sensor calibration is done at the beginning, followed by clutch and solenoid calibration at the end. If sensor values were out of the bounds, you would see that as another distance sensor error


edit:
which one of the below procedures have you done? Calibration after part replacement will do what PV997 mentioned, it uploads the default software and then performs the calibration.

PV997

Great point amet, I forgot there were two different calibrations. How do you know it uploads the default software, does it give you notifications stating this? Also, is your PIWIS live to Mother Porshce or a clone? I've only ever done the "calibration without part replacement" on a clone.

amet

my German is a bit rusty, but I remember seeing the file name of the binary file being uploaded…. Something to do with default if memory serves me well. Mine is a clone piwis and this step works for both calibrations using it “offline”.

PV997

LOL, I just looked up P1872 in the t-shooting diagrams and it says "perform calibration after part replacement". Hopefully it's that simple and I should have checked that first before writing a thesis on adaptation values. I think my explanation was correct and it does clear the values but sometimes folks just want to know how to fix it.

PV997

These are the standard over temp faults and aren't unusual during heavy duty track use, it simply means the clutch fluid in the sump has gone above the limit set by Porsche. Check out LN engineering for a heavy duty PDK clutch fluid/water exchanger. There's also an aftermarket pump/cooler that can be added to the PDK gear oil section, neither the 997 or 987 came with one. Porsche added a gear oil cooler in 2013 to the 991/981 as standard equipment I suspect in response to heat-related complaints.

Niklas Vemdal

Slow progress but at least some progress.

I tried to split transmission without a proper tool only using steel and two 2 armed standard bearing removers. Didn’t work out for me. I got a proper tool produced, don’t have enough nice equipment when I temporarily live in US. I used this drawing / dimensions:




I have now opened the transmission, it went very smooth without any “jumps”. Sealing also in very good shape. I’m now looking forward to replace the displacement sensor. Transmission is still in the car (Boxster 987.2) and I have full access.

Kuro Neko

Excellent stuff.
What is the production date and batch / serial number of your dead sensor?
This is mine:

t-design

It's ridiculous how good those gears look after who knows how many miles!

PV997

Thanks for the puller sketch Niklas Vendal, very helpful.

Switching topics, I've been thinking about the upthread comment regarding calibration issues after replacing the distance sensor. Bottom line is that things are not always going to go smoothly which is why we've all spent a lot of time in this thread documenting how things work rather than just telling people what to do. We don't know all the answers and the PDK is a complex beast. The hope was that if people understand how it works they can figure out how to deal with unforeseen situations. They would then pay it forward by posting what they've learned.

When this thread was started in Dec 2019 there was not a single post anywhere on the internet that discussed PDK internals in detail AFAIK. There certainly was nothing that showed how to open the gearbox up. This despite the transmission being ten years old. Eighteen months later folks are opening and repairing their PDKs in their garage. Pretty amazing.

T-design has provided a part that literally allows folks to save $10,000 in PDK replacement costs. No one should expect that kind of benefit with a foolproof 1-2-3 DIY summary as we are all blazing new ground here. Porsche has made none of this info available and has impeded attempts to figure it out. Porsche dealerships are absolutely worthless regarding any of this and no help whatsoever.

If folks don’t want to deal with some uncertainty or risk then there is any easy solution, pay a Porsche dealership $15k or more to replace the transmission. One doesn’t get a $10k savings without getting your hands dirty and having to think for yourself. Shots at T-design’s “quality control” or “standing behind their product” aren’t helpful unless one it sure the part is broken. The distance sensor output can be strip charted with a PIWIS so this question can be easily settled, there is no need to speculate. Yes the part is expensive and folks like things simple and foolproof but compare the cost to the savings of not needing a new PDK.

I have no affiliation with T-design but am grateful they stepped up and provided an option where none existed.

t-design

removed by author

Pinkawa

Thank you PV997 - I specifically told the shop this but I will double check.

You mentioned that you heard of a new PDK control unit may be required after PDK gearbox replacement - I could not find anything on this.
Would be nice to know how many of the T9 sensors are put in cars and how many needed calibration and how many needed actually a new PDK TCU - if that is really requires in some case would have been nice to know upfront.
But I hope the calibration will fix that and the shop made a mistake.
I will keep you posted.