porsche pcm system problems can anyone help as porsche will not

[alland]

This seems to be a very common problem. I have a 2006 CTT which was having intermittent loss of the PCM with the error message "Nav, amp, CD..... not available". After I intalled the Mobridge BT module on the weekend the problem became constant with the error message remaining on the screen whenever I switch it on. I hooked up the Durametric and it gave me the following codes: 459 - PCM No signal and 532 - Power Supply Short to ground/pos.

I have an appointment at the dealer tomorrow to try to further troubleshoot the problem. As has been pointed out the fibre optic cable is quite fragile.... could it be that the intermittent symptoms were caused by a kink in the wire that was made worse when I re-installed the head unit? .... or could I have shorted out the power supply when I connected the Mobridge module to the power supply on the back of the head unit. I followed the instructions on their website video and used their connectors but anything is possible. Funny how common this problem seems to be though. makes me doubt that it was anything that i did on the install. One last question, would adding the Mobridge unit void my aftermarked warranty if I need to replace one of the factory components (eg amp, headunit, fibreoptic cable...)?

[ILoveheat]

Hey, same problem here: I have a 2004 Cayenne, and pretty much I have the same problem, the error message that says "...amplifier no available". the navigation works, but no audio at all. I disconnected the CD changer, and nothing changed, but the message that only says that the amp doesn't work. Now, it started with intermitten frequency, a day it was working, the other it wasn't. I turned off the engine and restarted it and it was working. Loud noise and stopped working, not working at all. Now it hasn't worked for a month, and yesterday once gotten to destination, I stopped the engine, removed the key, and thought to start the radio and ...bang, it worked! I repeted the experiment today after the 16 miles trip to the office and it worked again. So what the F... is going on? it's not the amp, it's not the optical cable in my opinion, it's not the fuse....what the heck is it?

I thought it could be a ground problem. Not at the battery though, I had the battery replaced a week ago, and thus (I want to hope) the job was done correctly and all nuts and bolts were tightened. so.... i checked the ground bolt in the rear of the vehicle, left and right in the trunk inside where you have those emplty spaces. they seem ok to me, so.... WHY WHY WHY all of the sudden? what is the cause? what is it?

[Deikoo]

Hey, same problem here: I have a 2004 Cayenne, and pretty much I have the same problem, the error message that says "...amplifier no available". the navigation works, but no audio at all. I disconnected the CD changer, and nothing changed, but the message that only says that the amp doesn't work. Now, it started with intermitten frequency, a day it was working, the other it wasn't. I turned off the engine and restarted it and it was working. Loud noise and stopped working, not working at all. Now it hasn't worked for a month, and yesterday once gotten to destination, I stopped the engine, removed the key, and thought to start the radio and ...bang, it worked! I repeted the experiment today after the 16 miles trip to the office and it worked again. So what the F... is going on? it's not the amp, it's not the optical cable in my opinion, it's not the fuse....what the heck is it?

I thought it could be a ground problem. Not at the battery though, I had the battery replaced a week ago, and thus (I want to hope) the job was done correctly and all nuts and bolts were tightened. so.... i checked the ground bolt in the rear of the vehicle, left and right in the trunk inside where you have those emplty spaces. they seem ok to me, so.... WHY WHY WHY all of the sudden? what is the cause? what is it?

I should check the AMP in the rear (right side of the luggage). My experience says that the hose for rear window washer is broke (in the sealing above the amp) and therefor it comes washer fluid on the amp.

[yukonriver roy]

I have a 2005 cayenne s. The PCM had been working fine up until the last few months. Nearly everytime you get into the car now and start it up the PCM comes on however the SAT NAV, AMPLIFIER and PHONE will not work.

A message stating

SYSTEM ERROR

PHONE, NAVAGATION & AMPLIFIER NOT AVAILABLE.

I spoke to the specialist at my local Porsche dealership about this and he said he would need to get the car onto the diagnostics to identify the fault.

I arranged to bring the car down to him when the fault appeared again.

As i stated this problem occurs nearly everytime you get into the car, however there are times when you get in turn the ignition on and the system works ok.

On three separate occasions i brought the car down to my local porsche dealership when the fault occured, but on each occassion ie ( after i got out of the car, locked it and went into find the service manager and came back out to the car) it had reset and was working. Making me to look like an absolute twat.!!!

Last week i was able to get the car onto the diagnostics when the fault occured. To my surprise and the service managers surprise no faults were being registered, even though the system error message was clearly visible on the head unit.

Stephen the service manager spoke with the head service specialist at the dealership and he said that in his opinion he thinks the problem lies with the BOSE AMPLIFIER in the boot.

Of course an AMPLIFIER isint cheap £800 fitted i believe, and this mighnt even been the cause of the fault.

Stephen therefore said he would speak directly with Porsche in Germany and the UK to see if they had come across problems like this before and whether they would be prepared to provide an Amplifier on SALE OF RETURN. IE if it isint the cause of the fault they would let him send it back.

To say neither Porsche UK or Germany were helpful is an understatement. Both said they had never came across this problem nor would they be prepared to provide an AMP on sale of return.

The fact i paid £58,000 for the car and have had it serviced and maintained (at great expense) through Porsche doesnt seem to matter.

I now have the choice of putting up with it or paying £800 for an amp with the real possibility the one i have is not causing the fault.

I am therefore looking to see if anyone has had problems like mine with their PCM, what caused the fault and how the fault was diagnosed.

Or even any ideas as to what the fault might be with mine from what i have said.

:welcome:

Please state your location - and perhaps someone here with a PST2 or PIWIS can check it for you.

Good day. I came across this little piece of heaven yesterday after experiencing the very same problem described above. I own a 2008 Cayenne S. It had occurred maybe four times over the past two years but only for the duration of the trip. When I next restarted the car everything worked. This time not. For two days I heard nothing but the wind whistling over my ski rack (that's another story) and was not happy. I live 2000 km from the nearest dealer and when I called and described the problem, they "suggested" I call the audio specialist down the street. I googled the error and found this site. I ended up pulling the #9, #10, #11, and #12 fuses from the passenger side panel, cycled the locks, and waited 10 minutes. When I installed the fuses and turned the key everything was back. So far so good. I believe the issue is software related and the system gets hung up like a program or mouse on a computer. The system needs to be rebooted and involves more than recylcling the ignition. The latent power in the system needs to be removed just like a computer. Thanks again for putting the smile back on my face. I am your newest member.

[bigbuzuki]

The PCM system can be also reset by an easier method instead of pulling fuses etc.

Simultaneously pressing the 1,4,8 numerical keypads on the PCM headunit will initiate a reboot of the system.

Edited March 22, 2010 by bigbuzuki

[bazdubai]

I have a 2005 cayenne s. The PCM had been working fine up until the last few months. Nearly everytime you get into the car now and start it up the PCM comes on however the SAT NAV, AMPLIFIER and PHONE will not work.

A message stating

SYSTEM ERROR

PHONE, NAVAGATION & AMPLIFIER NOT AVAILABLE.

I spoke to the specialist at my local Porsche dealership about this and he said he would need to get the car onto the diagnostics to identify the fault.

I arranged to bring the car down to him when the fault appeared again.

As i stated this problem occurs nearly everytime you get into the car, however there are times when you get in turn the ignition on and the system works ok.

On three separate occasions i brought the car down to my local porsche dealership when the fault occured, but on each occassion ie ( after i got out of the car, locked it and went into find the service manager and came back out to the car) it had reset and was working. Making me to look like an absolute twat.!!!

Last week i was able to get the car onto the diagnostics when the fault occured. To my surprise and the service managers surprise no faults were being registered, even though the system error message was clearly visible on the head unit.

Stephen the service manager spoke with the head service specialist at the dealership and he said that in his opinion he thinks the problem lies with the BOSE AMPLIFIER in the boot.

Of course an AMPLIFIER isint cheap £800 fitted i believe, and this mighnt even been the cause of the fault.

Stephen therefore said he would speak directly with Porsche in Germany and the UK to see if they had come across problems like this before and whether they would be prepared to provide an Amplifier on SALE OF RETURN. IE if it isint the cause of the fault they would let him send it back.

To say neither Porsche UK or Germany were helpful is an understatement. Both said they had never came across this problem nor would they be prepared to provide an AMP on sale of return.

The fact i paid £58,000 for the car and have had it serviced and maintained (at great expense) through Porsche doesnt seem to matter.

I now have the choice of putting up with it or paying £800 for an amp with the real possibility the one i have is not causing the fault.

I am therefore looking to see if anyone has had problems like mine with their PCM, what caused the fault and how the fault was diagnosed.

Or even any ideas as to what the fault might be with mine from what i have said.

[bazdubai]

well I have now been without sat nav stereo and ph system since Nove. Porsche in the UAE (Dubai) are wonderful people (not) although from other peoples experiences it would appear customer service is not a word in the German Porsche vocabulary!! Love the car but hate the people behind them. haing been booked in 2 weeks ago and arrived to have a new PCM module fitted (this is what they believe is the problem- I am not so sure) they apologised and said that they had the wrong part. How long does it take to order and deliver a part ...Nov till now!!! crazy anyway it goes in tomorrow at a cost of 7000 aed for the part! I am not expecting it to be working, but stranger things have happened.

Will update tomorrow if I get the chance

Baz

[mudman2]

Thats why people switch to the mobridge unit. Much better integration

[claudior]

The Cayenne is a freaking nightmare, electronic wise. The main reason why I got rid of my 2006 one, as soon as the warranty was over. The car is NOT made for cold climates, guaranteed. From December to March we have temperatures all the way down to -30/-40oC and the Cayenne was the only car I could not park outside my garage. All other cars would start, no warnings on the dash, nothing. The Cayenne would give me ALL sorts of issues when it was cold. As mentioned, these issues would show up in the dashboard but NEVER on the computer log so the dealer could never find anything wrong and always tried to make me pay for their time trying to 'diagnose' it. Until the day I took PICTURES of the dash and brought to the dealer. Since that day they NEVER even tried to mention the words 'you owe us...'.

Great car in several ways and I really loved it and missed it a lot. But as an engineer, I cannot live with bad engineering, especially on the electronics side, what Germans are well known for screwing up. They may be great mechanically but not electronically.

If you never had an electrical/electronic issue with your Cayenne, it will come. Guaranteed.

CR

[Harry4fish]

i have a 997 carrera when i turn the car on the pcm works ok for about 1 minute then switches off ! .......then sometimes back on again..........then off again, then eventually i get the message saying the telephone, satnav, amp etc are not working! going in to porsche chester on wednesday !

[ManMN]

I bought the car used (04 CayenneS - standard audio - no NAV). At the time I took delivery of the car, the dealer informed me that the amp is bad & gave me $500 discount... I bought a used amp on ebay, changed it out myself (it was a task!), solved the problem! sounded great!... about two months ago, I got no sound. I brought the car to the dealer for battery issue and ask them to check the audio system. Sure enough, they said the amp is bad!

I really don't want to replace the amp again, instead, I want to upgrade to an aftermarket (Kenwood or Pioneer) system but I read a lot about getting error code if I'm not using the factory amp! is it true? What options do I have? I prefer to install new system myself if I have wiring diagram.

Can anyone advise me?

Thanks,

ManN

[nhirsch]

Making me to look like an absolute twat.!!!

I think you meant twit instead of twat! LOL. Sorry can't help with the problem.

Edited September 1, 2012 by nhirsch

[deilenberger]

For all this is worth - I recently installed a Dension Gateway 500 unit in the trunk of my 2006 Cayenne Turbo. Ever since - occasionally the PCM reports phone, navigation not working. I believe the problem lies with the optical wiring and the way data is exchanged between various modules in the loop. The dension unit / wiring connection obvioulsy causes havoc. Here´s what i found out that is interesting - if I switch audio source to RADIO - turn off ingnitiation and PCM and restart- the problem usually occurs - but not if i turn the PCM off with the CD changer (ie. IPOD interface). It must have something to do with amplifier module and headend radio / other modules getting information in some order. Atleast i know how to avoid the problem.

Where did you get the required constant power for the GW-500? If you're using switched power for it - that is likely the cause of your problems. It takes a moment for the MOST receiver/transmitter to wake up and pass the fiber signal on, so it initially thinks there is no signal downstream from the GW500, so you'll see items error out. Having the GW-500 on continuous power keeps the MOST receiver/transmitter part powered on continuously, so there is no delay on passing the signal on.

IIRC there are notes on Denison's website somewhere which also talk about what order the MOST units have to be in. I seem to recall them wanting you to put the GW500 before the amplifier in the fiber loop (but I could have that backwards..) Mine is mounted up front under the dash, and is the first MOST device in the fiber loop... works fine each and every time.

[hahnmgh63]

Harry4fish, sounds like you have a Fiberoptic connection that is loose. That used to happen to my '06 Turbo S and I found the loose connection behind the glovebox where the dealer installed (NavTV) Ipod box was plugged in. I thought it was my Mobridge connections that I put in the right rear where the OEM CD Changer was and was constantly checking them until I finally found the problem, a little tape to keep it from coming loose again and never a problem since.

[gwbeers]

I'm the recent second owner of a 2008 Cayenne S. I'm having trouble with the PCM 2.1 system. The system software is 4.1, the Nav DVD is 08.2007, Part #997.044.901.51/955.044.902.61. The PCM head unit displays an "overheat" message and turns itself off after approx. 20 seconds. When manually turned back on, it remains on with access and function to the Bose amp, cd changer and single disc player in the head. The navigation DVD player accepts the DVD mechanically, but the PCM says the DVD is not readable. I removed the Nav/DVD player and sent it to Hitech in Van Noys, Ca. where it was bench tested and no problems were found. With the player removed, the light path is open so the PCM doesn't see the amp, cd player or changer, however the Head unit stays powered on, with no "overheat" message. My dealer said it's "probably" the PCM unit - $4600 new or $2700 refurbed. Where do you think the problem lies? (other than dealer incompetence)

Edited September 9, 2012 by gwbeers

[Natty]

Don't know if this has been mentioned but when doing research on how to replace the battery on my 04 Cayenne, I noted with interest that some PCM/Amp issues were being attributed to a failing battery.

Having bought a refurb PCM a while back, which was working fine, I started to get intermittant Amp error messages. Dealer said I need a new Apm. I was not happy.

Shortly after that, I changed the battery. Lo and behold, I haven't gotten an Amp error message since...not one.

[dcyao2]

One more data point... 2006 CS. Battery changed last month. Spontaneous "System Error..." message. Lost Nav, Amp, Phone. Tooki Satellite Radio and Bluetooth had been installed years ago. I temporally associated this error message with wife's plugging lactation pump into cigarette lighter and then losing power to central lighter sockets the day before.

Replaced fuse #1 at left panel. And... problem solved! Thanks to others who have contributed here!

[M3 Defector]

One more data point...

 

2006 CS.  Battery changed last month.  Spontaneous "System Error..." message.  Lost Nav, Amp, Phone.  Tooki Satellite Radio and Bluetooth had been installed years ago.  I temporally associated this error message with wife's plugging lactation pump into cigarette lighter and then losing power to central lighter sockets the day before.

 

Replaced fuse #1 at left panel.  And... problem solved!  Thanks to others who have contributed here!

I know it has been a long time since this post, but which row fuse #1?  By left panel do you mean the one in the driver's footwell?  My PCM is not responding at all after changing batter.  I did touch the battery posts incorrectly for a moment and blew fuse D10 (25 amp) but replaced it and still no joy.