2009 Cayenne Turbo S

Ok. Here's what has been my issue. At completely random times after startup, the compass display next to the left of the on board computer would be blank. Everything on PCM 3.0 would be fine.

So I tried to look under the rear right seat where the compass module was supposed to reside. All I could find though was a silver colored box that was confirmed to be the pdcc regulator.

So I looked at the fuses and found fuse 36 in the right hand fuse box. It's a 5A fuse and the description is "roof module, telephone, compass." Just for the heck of it I pulled the fuse to see what would happen. All I can tell is ever since I have done that, my compass has been showing up every single time, and I have has no loss of functionality with the roof console and/or phone.

NO clue why this might be the solution, but the dealer replaced the instrument cluster about a year ago to fix the problem, but to no avail. I wonder what this fuse is for and if it was causing another module to interfere with the dash display?

 

Seems odd that pulling the fuse would make it work!? Everything else that was listed on that fuse still work?

 

sounds very interesting

 

Yep no changes to anything. Everything else is working. Not sure what the fuse is even for???

 

Yeah so this didn't work. My magnetic sensor module must be going bad. Where the heck is it in the 957 CTTS? I looked under the rear seat, but it's not there? Emailed suncoast and the didn't know either!!

 

OK, I've been doing extensive research on this issue. I've contacted ECS, Pelican, Suncoast, etc to figure out where the magnetic field sensor is on my car. No one seemed to know. My dealer said they would get back to me, but never heard back from them. If you look at the parts diagrams, it's not clear where it is. But here is what I think is the issue.

I looked at the order guide for the 2009 Turbo S. In the listing of the options, the compass module is an OPTION only for those cars without PCM 3.0. It clearly lists it as a conflict to the PCM 3.0 option. So this leads me to believe that if an 09 or 10 has the PCM, there is not a separate compass module. The 2008, i believe, has the PCM 2.1 as an option, even though it's considered a 957. So on this model, even if it has PCM 2.1, there is still a compass option.

I believe that somehow the PCM on the 09s and 10s feeds the instrument cluster with the compass feed. So I've concluded that there must be an issue within my PCM (or the wiring) that sends the info.

Most of us obviously do not have a PIWIS readily available, so i don't know what I can do from here. Been toying with getting a map upgrade so I can update my 1.40 software, but have read mixed things about the upside vs downside of doing this upgrade, as it could create more problems. And it begs the question as to why I even have a fuse in the 36 spot stated above. Frustrating.