Bill P.

I just had my Cayenne detailed (same guy I’ve been using for years and he’s very fastidious) and the PCM unit is now shutting down and immediately restarting from the Porsche Logo/white screen every two or three minutes. I’m pretty certain he didn’t have anything to do with it. He says he didn’t spray directly onto the unit. He didn’t have the keys either. I’m pretty satisfied its just a coincidence.

Its now also difficult at times to switch between AM/SiriusXM or between stations (buttons not responding or responding slowly) though this is much more intermittent than the constant restarting.

Has anyone else had this issue??

touareg

Try checking the DVD, when mine started going bad, it started rebooting the unit (Assume you have the newer unit with the DVD under the passenger side)

EDIT: NVM, see you have a 2011, newer car not PCM 2.x

Bill P.

Thanks anyway, touareg.

As an added data point, the radio also stays on now after shutting down the Cayenne. I does shut down eventually.

CAVU

Did you ever solve this problem? If so, how.

BlazinPond

Mine just started doing this today on my way back from work.
It worked perfectly on the way to work but not the way home (about 30-minute drive).
Nothing out of the ordinary from yesterday to today.
This has happened one other time about 3 months ago, but
the restart only lasted twice over the course of about 5 minutes.

Good grief...

CAVU

We are on an extended road trip and yesterday it started a reboot about every 2-5 minutes. after about 6-7 of them I shut off the Bluetooth and all was well. Later on, after a vehicle shutdown and start cycle, same thing started again, except Bluetooth made no difference. It's all under CPO warranty but what a pain. Different issue on my 911 that required a new PCM. Just got off the phone with my service advisor. He stated there are a couple of possibilities and one is related to what happens when XM drops a satellite and tries to reacquire..."buggy software...not much you can do except disconnect Bluetooth devices, turn the PCM off and on...." Oh well.

CAVU

So the CS sat unstarted for about 12 hours. Started it this morning and no issues with the PCM. Does the PCM have different boot sequences that are driven by when it was last driven?

stumil

My 2011 Cayenne S is doing the same rebooting process. Happens about 20 times an hour. Started 3 days ago. Quite annoying. Taking it to dealer next Tuesday.

CAVU

Mine started Tuesday afternoon. Same day for you?

RedStorm

Have you check the battery? From what I have read here - it may be time to change the batteries.

jfr0317

Our 2011 Cayenne S has recently started doing the same every 2 to 3 minute PCM rebooting. I just called my dealer, and he says it is a result of a recent XM Radio over-the-air software update. He says the fix is for the dealership to update the car's software. I'll report back after getting that done if it solves the problem.

airbil

I had this reboot reboot reboot problem last year and the fix was to send to Becker in NJ.
I don't really know what they did but it appears they installed a new screen and supposedly some new software. Yes it was $750. OUch, but I bought this fine truck so inexpensively I just considered a hit to part of the savings.
I may have opted for the Dynavin $850 solution which is better in some ways but not in others... had that been a little more tried and true back then.
Anyway, when mine was broken, if I left a small ceramic heater blowing in there to keep the cabin warm, the PCM would always work fine. This told me it was temperature related to some weak component. Tried as I might, I couldn't find anything after 2-3 attempts taking it apart and putting it back together.
It "may" be worth "taking one for the team" to install a new screen off ebay to see if that fixes this, but that's a $150-200 crapshoot.
HTH

TonyJF

I have the same issue with the PCM shutting down and restarting every couple of minutes. I spoke with my service manager and he said I was the 7th straight caller with this issue. He said it has to do with the new IOS update pushed down to us iPhone users recently. He recommended doing a complete shutdown of the iPhone (pressing and holding both buttons). I tried this and it seems to work. I drove nearly a half hour with the iPhone completely shut down and the PCM didn't reboot once.

Of course this doesn't solve the problem of now having no phone in the car!

CAVU

so today it rebooted twice and the wife's iphone was not in the car. pcm bluetooth remains off. 14 hour road trip tomorrow so we'll see what happens.

pwhite52

Same issue here. Started the reboot reboot reboot on Tuesday of this week. I called the dealer and they confirmed it appears to be linked to Sirius XM. I was told Porsche is aware and has a software fix. Mine goes in next Tuesday for the update and hopefully that solves it. Just purchased last Friday ('11 base version but has virtually every option but PASM) so this was making me nervous.