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porsche pcm system problems can anyone help as porsche will not


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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.

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  • Admin
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.

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I have hear of this before. There is a slightly bad Fiber connection on the MOST bus or there is a kink in the fiber somewhere. I would bet the rear amp cdc connectors unless you removed the PCM for some reason, then I would check the plug in the back.

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.

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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.

hi UK NORTHERN IRELAND, as i have said it has been on the diagonstic system at PORSCHE BELFAST and it displayed no faults on the diagonstic system even though it was displayed on the pcm

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I have hear of this before. There is a slightly bad Fiber connection on the MOST bus or there is a kink in the fiber somewhere. I would bet the rear amp cdc connectors unless you removed the PCM for some reason, then I would check the plug in the back.

Hi i dont quite understand what you are saying, i can confirm the pcm was never removed

what should i be checking for here?

thanks

Edited by tigerd
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There is a fiber optic loop running from device to device, if one of the connections is bad the circuit is broken and PCM says it cannot detect the systems. All the connectors need to be checked BUT the front seems the most obvious

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There is a fiber optic loop running from device to device, if one of the connections is bad the circuit is broken and PCM says it cannot detect the systems. All the connectors need to be checked BUT the front seems the most obvious

ok could you send me a pm mate regarding this, am i correct in saying i need to remove the head unit and check the connections there? or do i need to check the fibre optic loop from the amplifier?

thanks

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  • 3 weeks later...
  • 2 weeks later...

I too am having the similar problems. I had some professionals install the DICE Ipod adapter. This only happens after the car sits a while and mostly when the temp goes below 32F overnight. I get a CD CHANGER not found.

So I drive my car 5 minutes, pull over, shut my engine off and remove the key. Wait 1 minute, start the car back up and guess what, the IPOD adapter is fully functional.

Sometimes the IPOD or regular head-unit CD player loses it place and time if the car sits over night. This never has happened in my heated garage.

Brought this into Porsche once, they say my AMP has an error code and I replaced it.

Only once since has my AMP not been found. Still happens. I have a 2004 Cayenne-S with NAV, no real CD-changer.

How does one check for a “slightly bad Fiber connection”

What is a “PST2 or PIWIS”

I love my music almost as much as my car, is it worth trying another PCM head-unit? I bet I can find one used under $1000.

Mudman2- When you wrote “My temp Fiber bypass of CDC”, was this temperature or temperature. Wondering if this part could fix my issue.

Many thanks for I am at wits end!!!

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What your describing is slightly different from the original writer.

When you add a device like the Dice to the MOST network, timing the power up of the device is critical. If the Dice does not have a permanent power connection to it, when the car starts its pre flight the MOST circuit does not see the component and will throw the error.

It takes a while after you shut the car off before all the systems shut down. I don't think its temperature related at all a coincidence maybe.

I would check to make sure it has a non switched power supply so its primed and ready when the car systems come up.

PIWIS / PST2 are Porsche shop testers (computers) used to do almost everything on the 30+ computers on the car.

Its not your head unit. The DICE unit simulates a changer

Not to familiar with the DICE unit, I use Mobridge. Not much discUssion on DICE i.e. not a good system

I too am having the similar problems. I had some professionals install the DICE Ipod adapter. This only happens after the car sits a while and mostly when the temp goes below 32F overnight. I get a CD CHANGER not found.

So I drive my car 5 minutes, pull over, shut my engine off and remove the key. Wait 1 minute, start the car back up and guess what, the IPOD adapter is fully functional.

Sometimes the IPOD or regular head-unit CD player loses it place and time if the car sits over night. This never has happened in my heated garage.

Brought this into Porsche once, they say my AMP has an error code and I replaced it.

Only once since has my AMP not been found. Still happens. I have a 2004 Cayenne-S with NAV, no real CD-changer.

How does one check for a “slightly bad Fiber connection”

What is a “PST2 or PIWIS”

I love my music almost as much as my car, is it worth trying another PCM head-unit? I bet I can find one used under $1000.

Mudman2- When you wrote “My temp Fiber bypass of CDC”, was this temperature or temperature. Wondering if this part could fix my issue.

Many thanks for I am at wits end!!!

Edited by mudman2
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  • 2 weeks later...

Mudman-thanks for the suggestions, here is what I found

1-The DICE is wired into the PCM, so both are always switched, right?

2-Temp is a factor, the last week its been cold, (you know being from Bucks) and the Dice was never recognized, once even the AMP

The last 3 days its been warm, every morning and afternoon now the DICE has been recognized.

3- Once I have had a minor issue, both the CD in the PCM and the IPOD lost their time place.

Do you think that maybe my car battery is going bad?

I was thinking about trying another DICE?

What about trashing the DICE and going with Mobridge?

Any thoughts, thanks

PS-Thanks for the "Swap Air Filters" help, did that this warm sunny Saturday

What your describing is slightly different from the original writer.

When you add a device like the Dice to the MOST network, timing the power up of the device is critical. If the Dice does not have a permanent power connection to it, when the car starts its pre flight the MOST circuit does not see the component and will throw the error.

It takes a while after you shut the car off before all the systems shut down. I don't think its temperature related at all a coincidence maybe.

I would check to make sure it has a non switched power supply so its primed and ready when the car systems come up.

PIWIS / PST2 are Porsche shop testers (computers) used to do almost everything on the 30+ computers on the car.

Its not your head unit. The DICE unit simulates a changer

Not to familiar with the DICE unit, I use Mobridge. Not much discUssion on DICE i.e. not a good system

I too am having the similar problems. I had some professionals install the DICE Ipod adapter. This only happens after the car sits a while and mostly when the temp goes below 32F overnight. I get a CD CHANGER not found.

So I drive my car 5 minutes, pull over, shut my engine off and remove the key. Wait 1 minute, start the car back up and guess what, the IPOD adapter is fully functional.

Sometimes the IPOD or regular head-unit CD player loses it place and time if the car sits over night. This never has happened in my heated garage.

Brought this into Porsche once, they say my AMP has an error code and I replaced it.

Only once since has my AMP not been found. Still happens. I have a 2004 Cayenne-S with NAV, no real CD-changer.

How does one check for a “slightly bad Fiber connection”

What is a “PST2 or PIWIS”

I love my music almost as much as my car, is it worth trying another PCM head-unit? I bet I can find one used under $1000.

Mudman2- When you wrote “My temp Fiber bypass of CDC”, was this temperature or temperature. Wondering if this part could fix my issue.

Many thanks for I am at wits end!!!

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1 - If the Dice is switched with the PCM then that is wrong. The Dice should have constant power in order for it to be ready when the MOST bus starts up and it can be recognised.

2 - sounds just inconsistent

3 - wow, do you mean on the display or there position in a song

if your model is over 4 I would think battery maybe but other things would be going also, I am on my original battery still.

if you can afford it I would switch to Mobridge

Mudman-thanks for the suggestions, here is what I found

1-The DICE is wired into the PCM, so both are always switched, right?

2-Temp is a factor, the last week its been cold, (you know being from Bucks) and the Dice was never recognized, once even the AMP

The last 3 days its been warm, every morning and afternoon now the DICE has been recognized.

3- Once I have had a minor issue, both the CD in the PCM and the IPOD lost their time place.

Do you think that maybe my car battery is going bad?

I was thinking about trying another DICE?

What about trashing the DICE and going with Mobridge?

Any thoughts, thanks

PS-Thanks for the "Swap Air Filters" help, did that this warm sunny Saturday

What your describing is slightly different from the original writer.

When you add a device like the Dice to the MOST network, timing the power up of the device is critical. If the Dice does not have a permanent power connection to it, when the car starts its pre flight the MOST circuit does not see the component and will throw the error.

It takes a while after you shut the car off before all the systems shut down. I don't think its temperature related at all a coincidence maybe.

I would check to make sure it has a non switched power supply so its primed and ready when the car systems come up.

PIWIS / PST2 are Porsche shop testers (computers) used to do almost everything on the 30+ computers on the car.

Its not your head unit. The DICE unit simulates a changer

Not to familiar with the DICE unit, I use Mobridge. Not much discUssion on DICE i.e. not a good system

I too am having the similar problems. I had some professionals install the DICE Ipod adapter. This only happens after the car sits a while and mostly when the temp goes below 32F overnight. I get a CD CHANGER not found.

So I drive my car 5 minutes, pull over, shut my engine off and remove the key. Wait 1 minute, start the car back up and guess what, the IPOD adapter is fully functional.

Sometimes the IPOD or regular head-unit CD player loses it place and time if the car sits over night. This never has happened in my heated garage.

Brought this into Porsche once, they say my AMP has an error code and I replaced it.

Only once since has my AMP not been found. Still happens. I have a 2004 Cayenne-S with NAV, no real CD-changer.

How does one check for a “slightly bad Fiber connection”

What is a “PST2 or PIWIS”

I love my music almost as much as my car, is it worth trying another PCM head-unit? I bet I can find one used under $1000.

Mudman2- When you wrote “My temp Fiber bypass of CDC”, was this temperature or temperature. Wondering if this part could fix my issue.

Many thanks for I am at wits end!!!

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  • 2 weeks later...
1 - If the Dice is switched with the PCM then that is wrong. The Dice should have constant power in order for it to be ready when the MOST bus starts up and it can be recognised.

2 - sounds just inconsistent

3 - wow, do you mean on the display or there position in a song

if your model is over 4 I would think battery maybe but other things would be going also, I am on my original battery still.

if you can afford it I would switch to Mobridge

1) That's the way DICE was designed.

2) Since its been warm in the last two week, I have not lost my IPOD yet. Great!!!

But when this cold, I can plug in the Ipod all I want and it is not recognized.

3) Loses position in a song. Both the CD in the PCM and the IPOD, but not too often

4) its a 2004, lets hope the battery is not failing. If this continues next winter I bet a Mobridge is in my future

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  • 5 weeks later...

I have a 2008 Boxster S with the same basic problem. I got a "System Error - Amplfier and Navigation System are not available." Here is the fix that I got for this from my local Porsche Dealer:

Pull out the fuse relating to the amplifier and navigation system. I actually pulled two out. In my car they were in row D, fuses #9 and #10. The fuse box is on the driver's side in front of the door. Remove the fuse panel. There is a little booklet inside that tells you about all the fuses and what they do. After you pull the fuse(s), lock the car and wait for one minute. Unlock the car, reinstall the fuse(s) and the problem is gone.

It worked for me.

Update: It failed again so the fix was only temporary. I took the car into the dealer. They replaced the amplifier and everything is now back to normal.

Edited by twitte
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  • 1 month later...

I currently have the problem. Sometime it works and other times it doesn't - there is nothing that seems to trigger it unless it's the phone sim card?!

Is the problem with the Bose Amp, the optics cables, the PCM?? Someone must know as there are many who face this problem.

Does changing the Bose amp solve it - if not then what?

Very frustrating!

Thanks for your feedback

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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.

I am having the same system error message but with my Navigation System. I tried inserting the Nav DVD into the Navigation deck under the front passenger seat but it wont accept it, almost as if the power to the Navigation deck is off. Anybody with advice?

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  • 1 month later...

Not sure if this is a help but I have the same problem on my 2005 Cayenne S and have noticed that it only happens when the tempeature is below 82 degrees F. If the car sits in the sun and warms up (around mid-day) both the Nav and amplifier work fine. Not that I mind the Navigation being down since it is pretty much useless anyway, but I miss my TUNES! Dealer says they suspect a fiber optic cable problem....$$$$$.... anyone solve this problem without spending big bucks/euros?

Edited by jrlecroy
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  • 1 month later...

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.

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  • 3 months later...

I have just encountered the same problem, no changes made to the system simply turned on and it failed to work, my local dealer in Dubai reckons it is a faulty ph module and as it is connected in line causes all the related systems to fail. I have the car booked in in Jan now but would love to get some feedback here as am wary of being charged an arm and a leg to have various bits replaced that may not be necessary by people who lack the real skills and interest to find out the real issue. Help indeed!! hope someone has an answer!?

Baz

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  • 5 weeks later...
I currently have the problem. Sometime it works and other times it doesn't - there is nothing that seems to trigger it unless it's the phone sim card?!

Is the problem with the Bose Amp, the optics cables, the PCM?? Someone must know as there are many who face this problem.

Does changing the Bose amp solve it - if not then what?

Very frustrating!

Thanks for your feedback

I finally decided to change the BOSE amplifier and this has solved all my problems - even though it cost me $1000 - better than having a brick!

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In the Cayenne, you have a MOST line that goes from the PCM (head unit) to navigation unit, BOSE amp, telephone, tv and other external components that are connected to the PCM.

When this fault (error) comes up, the MOST line is broken in some way. It can be the connections, yes. But most likely its one of the external components that are broken. When a externa component is broken, the MOST line is cut. If you want to test the components you need to have a MOST dummy that you plug in instead of, lets say the amplifier. If no error comes up, the amplifier is faulty. If it still comes up, try one of the other external components.

If the amplifier is broken, check if it has come water on it. If it is so, then you should check the rear washer system for leakage inside the car.

Sorry for my grammar but im from Sweden ;)

Edited by Deikoo
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  • 1 month later...

I finally got around to sending my PCM to Becker for diagnosis/repair. It turns out that the problem was software related, it was apparently competely corrupted and had to be reinstalled from scratch. To recap, the problem i was having was:

Configuration:

• Bose audio system

• Amplifier connected via MOST fiber optic cable.

• NO CD changer or any other MOST devices.

Symptoms:

• Audio will periodically cut out, sometimes (but not always) showing “Amplifier not available…” on display.

• Hear soft popping sound from speakers.

• Unit will not always stay powered on.

Attempts to fix:

• Checked all fuses.

• Replaced car battery which was old anyway.

• Checked MOST fiber cable by shining flashlight down one end, saw light brightly on other end of each cable.

• Checked all connections on back of unit and on amplifier, everything seemed solid.

• With unit almost completely removed I turned it on and played with each of the wires to see if there was a possible short in one of them. Didn’t seem to make a difference, unit acted the same as if it was mounted in place. Also tried this at the amp end.

• Took to local Porsche repair shop. They could not locate the problem and proposed replacing unit with a refurbished one for $1500 but could not guarantee this would fix the problem.

In the end it ended up costing about $400 which i guess is much better than $1500.

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I have heard about this before, it occurs mainly when somene tries to update the firmware and the power goes off before its finished

I finally got around to sending my PCM to Becker for diagnosis/repair. It turns out that the problem was software related, it was apparently competely corrupted and had to be reinstalled from scratch. To recap, the problem i was having was:

Configuration:

• Bose audio system

• Amplifier connected via MOST fiber optic cable.

• NO CD changer or any other MOST devices.

Symptoms:

• Audio will periodically cut out, sometimes (but not always) showing “Amplifier not available…” on display.

• Hear soft popping sound from speakers.

• Unit will not always stay powered on.

Attempts to fix:

• Checked all fuses.

• Replaced car battery which was old anyway.

• Checked MOST fiber cable by shining flashlight down one end, saw light brightly on other end of each cable.

• Checked all connections on back of unit and on amplifier, everything seemed solid.

• With unit almost completely removed I turned it on and played with each of the wires to see if there was a possible short in one of them. Didn’t seem to make a difference, unit acted the same as if it was mounted in place. Also tried this at the amp end.

• Took to local Porsche repair shop. They could not locate the problem and proposed replacing unit with a refurbished one for $1500 but could not guarantee this would fix the problem.

In the end it ended up costing about $400 which i guess is much better than $1500.

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