2013 Panamera 3.6L RWD, with 98K miles on it. The car was purchased from an Estate Sale - had a completely dead battery and wouldn't start when we first got it. New Battery, Oil Change + plugs/coils and the car ran perfect, for about 200 miles. Yesterday, it started throwing a PSM warning followed by the Transmission Fault, the car still drove but shifted rough ( I was about 2 miles from home and made it back just fine ). I hooked up my Autel to it and had a bunch of codes, but the main code was the P1872 fault for the PDK. Has anyone tackled this before? Reading on forums it seems to be (possibly) caused by a faulty Valve Body, possibly dirty Hydraulic Fluid? I tried to do a transmission Calibration, but the test/procedure fails when it gets to the "Hydraulic Test"...the warning light for the transmission comes back on as soon as that part of the sequence starts. If I reset the codes and battery, the car will run and drive perfectly for about 30 minutes (Hwy/City) after which the PSM and transmission light comes back on...Has anyone run into this issue before? Is it worth throwing a reman valve body at it? And hope it fixes it? Or buying a wrecking yard complete transmission? Any help would be greatly appreciated!

 

It's also common for the shift rod harness to fail... I have a spare unit, but it's for a 970 turbo, so unsure of compatability.
Read more here... https://rennlist.com/forums/panamera...placement.html

 

If the shift rod would fail, wouldn't that render the transmission dead? Like I said, I can reset the codes and the car will shift perfect for the next 40 miles or so.

 

The shift rod sensor appears to go out over a period of time... works, then doesn't, works, then doesn't, and finally dies. Similar to a leaky air suspension and hard starting issues w/HPFP pump.... they work until they don't.
I surely can't confirm this is your issue, but just sharing what seems to be a common failure as one gets to the 6-figure mile marker. And to be honest, not read of many failing valve bodies...
You can surely change the fluid and pan first...

 

Interesting, I may just look at getting a transmission out of a wrecker. Pricewise it would make more sense. By the time I change the fluid and replace the filter and valve body, I am half way there.

 

You can try cleaning the mecatronic.
See my DIY : HERE

 

Worth a try - is that code common with dirty fluid/clogged valves (mechatronic)? Also, if I were to throw a used transmission at it, is there a need to reprogram the TCM? Or is it a "plug-and-play" pretty much?