My 2013 991.1’s PCM software is at Ver. 4.31. My car is in the shop for other reasons, and I thought of asking my dealer to upgrade the PCM to Ver. 4.76, which I recently learned about and understand is the latest for the car. (Why my dealer never upgraded it when the car was in for its many annual services, I don’t know.) But tonight, I read about some people having PCM rebooting issues. My PCM has been fine, so now I’m wondering whether I should just leave well enough alone. Does anyone have any advice? What does Ver 4.76 do that 4.31 doesn’t, and is it worth the risk of screwing up the PCM? Thanks in advance for any thoughts anyone may have.

 

No issues with the 4.76 upgrade and has nothing to do with the PCM rebooting issues you've heard about. That was a Sirius/XM issue. If you can buy the CD you can install 4.76 by yourself. There is a YouTube thread. Just search 4.76 on this forum and you can find lots on it. Another has uploaded a zip file with the update.

 

Thanks. This is good to know and sets my mind at ease. Do you know what 4.76 fixes or adds to 4.31?

Thanks, too, for the heads-up regarding the 4.76 file online. I was aware of that, but after some thought decided that because my car is out of warranty it may be better to have the shop run the upgrade. If anything should go wrong, that will be on Porsche and not me. And, I'm hoping I won't be charged because the upgrade should've been done automatically by the dealer when my car was in for it's annual services during the warranty period.

 

https://rennlist.com/forums/cayenne-...-versions.html

 

Thanks!

 

Hey folks, resurrecting an old thread. Did you have luck funding the CD or the zip file for the update? Thanks!