Hello, I have a 2012 Panamera 4 (63k miles) with the PDK transmission and I am going to be removing and replacing the transmission control module due to error codes P1731 and P1732 codes that I cannot clear. When the problem occurred, I decided to replace the PDK shift sensor array inside the transmission along with the fluid (approx. 9 quarts of FFL3), transmission mount, and pan/filter assembly. The job was straightforward. After completion, I could not clear the codes with my Autel MS906BT scanner so, therefore, could not perform the complete recalibration process. I also get these odd AC, PSM, and DME-related codes which I can clear, however, many of them tend to return shortly thereafter. The codes are U0418, U0456, C12097, 002087, 00208A, 0700, and P1872, P1583. I'm not sure if these codes could be an underlying problem or just based on the same TCM circuits. The AC blows cold. The car is meticulously serviced and was running great until the dreaded transmission faults occurred. I performed the Engine Torque Loss Procedure and used the oil fill mode. I have not driven the car since replacing the shift rod array and the car is still in limp home mode. Reverse seems to be unavailable and the shifter reads perfectly through the gears in Live testing on the scanner but the transmission itself reads Neutral throughout the testing.

SO, in following the Porsche Service Manuals, the P1731 and P1732 codes are only related to 3 things; 1. The PDK Shift Rod Sensor Array (replaced), the wiring harness for same (this sounds unlikely and there were no obvious signs of damage), or the TCM. I will be replacing the TCM, however, the service manuals are very unclear on where the unit resides and what needs to be disassembled to access the unit. I have removed the driver's side sill plate and peeked around but I do not see the TCM. Do I need to remove the airbags and lower dash to access the TCM or is there an easier way? I don't want to start taking things apart that are unnecessary. I saw a video about TCM's getting cracked solder joints which sounds like a plausible problem but I cannot check until I remove the module. If anyone has procedural guidance here, I welcome the help! Also, if anyone has any troubleshooting advice, TCM swap information, or has seen other gremlins cause this problem, please feel free to comment. If you need any further information or diagnostic information, please do not hesitate to ask. Have a great day!

 

hello, I am familiar with the issue you’re experiencing and also faced with the 17xx codes not deleting. I have tried with my piwis2 software along with disconnected battery to drain the system. Both unsuccessful. My next attempt was the tcm module and from my understanding it’s located on the passenger side floor area under carpet which should be just a plug & play removal. Have you advanced anywheee with yours since posting ?

 

Just replacing this could fix it.
PDK module