Gathering some information for PDK transmission fault.
Last week son drove PTT to store, when came out said reversed out of park spot, and when shifted into drive it was acting as in neutral. Called me. Told him to turn car off, he did. Restarted and car drove just fine even though transmission fault still stayed on.
I scanned car after he returned, got errors all over the place (99% of them are because car was in sport mode and sport+ pasm). So most of these were tripped since PDK got fault so car was not allowed to have the sport modes.

Anyway, I scanned and the two errors that I saw were shift rod 1 sensor impausible signal, and shift rod 2 implausible signal.
After I cleared the codes, car drove just fine.

Then, couple days ago, took car for a quick battery charge 15 minute drive. Car again was in sport/sport+ suspension, and on way back (guess car warmed up fully by then), stopped at a light. At green, tried to drive but car acted as if it is in neutral.
So I went through the gears from D to P, back to D, back to P. Turned car off. Started car, and car drove perfectly fine then, even transmission fault error disappeared (still have to scan car to see if errors in memory).

So gathering my info. Saw few posts on this.
My battery was very questionable. Since starter went it was suspect last year. Kept it just because i was not sold on it being bad (tested ok). But over last 3 months, car got discharged fully, had to boost,and noticed the hatch on way down gave error, electronics like that on fritz especially if using Burmester at loud levels (son loved to do that and that is when I was noticing batt. issues). So this spurred me take battery today in. Tested and showed not far from bad on tester, but when I looked at one side of battery, it started bulging out.
So off i went spending another couple hundred on AGM battery. Just put it back in, drove car around neighborhood trying to cause issue was could not.

Hoping that is what it is, bad battery. Tomorrow I think I will put car up and check the level of PDK fluid. If it is low, could mean sensors may be heated even more. Saw some oil sweat around PDK pan last oil change. Tightened bolts a little, too cheap to spend another 500 to get new pan/oil (just did PDK fluid change maybe 25k miles ago).
If you have info, let me know. I was so hoping I wont be putting together more DIYs, but seems it was optimistic.

So far, if error comes back, I will need the PDK sensor array (about 650), maybe the harness (quite not convinced it is needed as it only provides physical connection, and if not damaged should be fine (about 200). Then would need the PDK pan (another 300), PDK oil (another 250).
Then I read I will need PDK recalibration (I could buy that when sensors are replaced, only thing these are solid state sensors, so nothing physical to calibrate, but we will see.

Any info will be greatly appreciated. Car drivable, but I am trying to spare it. After battery change I will try to duplicate issue to see if battery resolved it. FYI, Porsche is the World leader when it comes to making cars that are very sensitive to voltage/current levels when it comes to all its subsystems. 50% of all issues can be traced to weak battery. So I am really really hoping this is it. We shall see.

 

Fingers crossed

 

I replaced those parts in my car although not because they wore out but because mine was trying to impersonate a submarine. The repair shop that did this said that the harness and sensor array often go bad. I wouldn’t change the array and leave the old harness. .

 

I can't offer you a solution or meaningful advice, but I have experienced a similar situation with my 2014 Panamera GTS. Car has 40K miles and I have owned it for eighteen months with no issues whatsoever. Went for a drive with our local Porsche Club to see a large car collection and then to an annual race venue to see the cars and take photographs. It was a total of 140 miles round trip. Drove in "Sport" mode for a portion of the trip. The car drove normally with no problems until on the interstate coming home about five miles before my exit. Happened to looked down at the instrument panel/display and saw "Transmission Fault." There was no change in driving behavior as the car continued to drive as it did before the fault display. I wasn't sure what to expect and kept checking all the indicators and listening for noises and/or indications of transmission problems, but nothing as far performance had changed. I considered pulling off to the side of the busy interstate but the car continued to function normally so I continued to the exit.

Went down the exit ramp and stopped at the first traffic light. The display continued to show "Transmission Fault." The light changed to green and I pressed on the accelerator to go forward. Nothing happened except the engine rev'd as if it were in neutral rather than in "drive" as the selector indicated. I shifted to Reverse, Park, Neutral, and Drive, but the car continued to act as if it were in neutral. I was able to roll off the highway to a side street and tried the same sequence again with the same result. Then, I turned the key off and back on and restarted the engine and put the car in drive. The "Transmission Fault" was gone from the display and the car drove normally from that moment until I arrived home. All indications were that the car would probably continue to drive normally, but I was reluctant to drive it without some resolution of what had caused the fault and the resulting behavior of the PDK unit.

Thus, a trip to the local Porsche dealer (a good one) where I requested a full fault analysis and diagnosis (the car is under CPO warranty). I don't have the fault codes, but I suspect that they were similar to yours. The dealer attempted to recreate the problem many times without success even to the point of collaborating with Porsche Tech Support in Germany. The car continued to perform as expected. The only remaining suggestion was to perform the transmission fluid change which is 60K miles or six years, and re-calibrate the transmission and drive the car. That was three months ago. There have been no problems since then and the car continues to drive normally. It's a daily driver.

A couple of things to think about:
1) The "Transmission Fault" code was green in color on the display. There may be different levels of severity that can be reflected in fault codes. Some may be easily cleared and some not.
2) Portions of the drive on the interstate were in comfort mode and other portions were in sport mode, meaning there was occasional switching back and forth between the two while at speed.
3) Adaptive Cruise Control was also engaged while on the interstate with increases and decreases in speed sometimes adjusted manually via the stalk as I changed lanes, etc.
4) Perhaps it's possible that some combination of switching between Sport and Comfort modes while manually increasing and decreasing speeds in ADCC at Interstate speeds might result in a condition of conflict in the signals sent to and/or received by the PDK unit?

That's the total of my experience with this issue.

 

I checked PDK fluid level and it was ok.
Drove again, got the transmission fault again. Again, turning car off and restarting (this time 2 times), did the trick. Fault cleared and I came home.
I noticed that this fault occurs when I drive in sport mode. This would explain fault since in sport mode shift rods, travel and timing is different for speedier changes and driving.
In normal mode (which I would say I use about 75% of the time), I did not see this error.
The transmission fault I saw on cluster was yellow (yellow gears with yellow letter saying transmission fault).
Resolution (short term): part car, stop engine, wait few seconds, restart engine. Repeat if does not clear error 1st time. You will need to be maybe even 3 times to clear error.
Thanks for your info. My PDK fluid is relatively new, maybe 20k miles on it. So I suspect the sensors.

 

The only reason I question the 'harness faulty' is because mechanics are often very inclined to replace everything in vicinity to ensure customer does not return with another error. These harnesses are nothing but connectors with metal conductors (wiring), connecting components. it is very hard for a metal conductor to go bad. Would have to be way over current situation, or some mechanical damage, for wiring to go bad. Connectors themselves, maybe, but these are high heat and wet application, so I am not inclined to see them as first culprit.
On other hand, if sensors start going bad, they will work intermittently. These sit in the PDK for years, in wet and hot environment, so to me, as an engineer, that would be better place for issues then a wire or connector that is not manipulated often at all.
One thing I can do is maybe drain oil, replug harness and see if issue returns. that would save money but would take long time to convince me issue is gone. So not sure where I go next, probably replacing the sensors. We will see, if weather holds, I may just drain into new bucket, replug harness, and refill to do more testing.
Advice is always appreciated. Thanks.

 

Last week, as I was enjoying the car, with no error for many days, I was just driving and all of a sudden the transmission fault came on. Pulled over to gas station, turned car off, started back up, and transmission fault went away, car was just fine.
So after about 3 weeks or so of no errors, one came up.
Few days ago, I decided to do launches. Did 4 in a row. No errors, nothing at all, car pulls great. Since then still no error.

I have no idea what I should be doing about this. I do not want the error at all, so guess it would mean replacing the sensor pack. Advice? Thanks in advance.

 

Sounds like you fixed it.

 

As an update, since May I have not seen the transmission fault. Have driven in all modes, did multiple launches. No issues. This is driving me nuts. Do I buy the 1k part? Or just hold off. My thinking is do nothing, or at least change pdk pan/filter, and fluid.
Suggestions? Thanks.

 

I wouldn’t bother with the fluid change. Just live with it (its annoying, yes) until it becomes more frequent. Some other clues might be revealed along the way that may point to something other than the 1k part.

 

Don’t remove the pan they are one use only and if you have to to turn loom in the future you will replace it then. If you want to do anything spray the inside of the two transmission connections with deoxit or something similar as this is a more likely cause of intermittent errors

 

2011 Panamera 4. Same issue.
"The car drove normally with no problems until on the interstate coming home about five miles before my exit. Happened to looked down at the instrument panel/display and saw "Transmission Fault." There was no change in driving behavior as the car continued to drive as it did before the fault display. I wasn't sure what to expect and kept checking all the indicators and listening for noises and/or indications of transmission problems, but nothing as far performance had changed. I considered pulling off to the side of the busy interstate but the car continued to function normally so I continued to the exit.

"Went down the exit ramp and stopped at the first traffic light. The display continued to show "Transmission Fault." The light changed to green and I pressed on the accelerator to go forward. Nothing happened except the engine rev'd as if it were in neutral rather than in "drive" as the selector indicated. I shifted to Reverse, Park, Neutral, and Drive, but the car continued to act as if it were in neutral. I was able to roll off the highway to a side street and tried the same sequence again with the same result. Then, I turned the key off and back on and restarted the engine and put the car in drive. The "Transmission Fault" was gone from the display and the car drove normally from that moment until I arrived home. All indications were that the car would probably continue to drive normally, but I was reluctant to drive it without some resolution of what had caused the fault and the resulting behavior of the PDK unit."

Please let me know how you overcome this issue. Dealer says to replace the transmission which cost more than the value of the car.

 

Boldie,
The car (and transmission) drove normally after the restart which reset the transmission error condition and the error message on the display. I was reluctant to continue driving the car on a daily basis without doing a more thorough check on what may have caused the error condition. I took the car to the Porsche dealer and asked them to read the stored error code(s) and determine the cause of the fault. They could see the error code but could not determine what specifically triggered the fault condition. They suggested doing a transmission fluid change (earlier than scheduled in the maintenance cycle) and to continue driving the car while monitoring how it performed and watching for any future fault conditions. That was two years ago and there has been no repeat of the condition since that time. The transmission continues to perform normally as expected.

Has your dealer specified what exactly is wrong with your PDK transmission? What exactly did your error message on the display say? Was the error message text color "green," "yellow," or "red?"

 

it was yellow transmission fault. and also the engine sign come and going. When the dealer checked they could not find any codes. But once codes 1733 , 1734 came. Taking to the dealer again tomorrow.

 

I just went through very similar with my 970 4S. Reverse because neutral. Yellow faults, sports model faults, check engine. I lost first and second gear, but others worked. Dealer replaced 1 of the PDK solenoids. A few years back you had to buy the whole solenoid pack ($3-4k for parts) but now you can buy singles. Dealer did the work under warranty but seemed pretty straight forward chatting with the tech. I think the total bill was $1200 before warranty.