MJPereira

My PCM started shutting off and turning back on all the time constantly. The white screen comes up with the Porsche lettering and emblem and then shuts down and comes back on and I cannot turn off the PCM at all. It continuously does this the whole time I drive it.

Anyone else ever have this issue?

Edgy01

The only thing I can suggest is for you to pull the fuse for awhile (10 minutes) in the form of a major reboot and try this all again. I don't recall any others herein reporting this problem. Once in a while there are some intermittent issues but nothing so severe as you describe.

number9ine

Do you have nav or bose? Is there a disc in the PCM's CD drive? One or more of these things might be causing the issue, although if it keeps restarting itself over and over again it's likely internal. Does it happen in a regular cycle, or is it more sporadic? If the latter, maybe there's a short in the wiring harness. If the car isn't under warranty, I'd look around for a DIY radio removal and check it out for yourself. Otherwise head for the dealer.

While uninstalling an accessory in the MOST loop I discovered that if you power on the PCM unit while the Bose amp is disconnected it'll give you a warning message on the PCM unit. If you have Bose, try disconnecting the MOST fiber plug (two orange fiber optic lines terminating in a plug behind the Bose amp wiring harness behind the toolkit in the trunk). If the radio runs with the error message and doesn't reset itself, maybe the amp is the culprit.

Anything aftermarket installed, like LoJack, ipod adapter, radar, bluetooth?

RJC/SLC

I'm experiencing a similar problem in my 2009 Carrera S, but it happens sporadically. Took it back to the dealer for the "latest" software update; however, it did not correct the problem. They are ordering a new PCM even though the diagnostics don't show any faults. Hopefully the new unit will eliminate the problem.