PCM failure
05-21-2010, 10:40 PM
#16
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The FOT is soldered into the amplifier's digital printed circuit board assembly. It is by no means a user replaceable item, nor is it a Porsche replaceable item.
It is the 'connector' that the 2 plastic optical fibers (usually clad in orange) plug into on any MOST device.
You need to have some experience in electronics soldering in order to replace it....and of course you need a new FOT.
There is no guarantee that is your problem, since there are other things that could be causing it, like a cold solder joint on any of the IC's involved in the digital audio path (and there are many).
It could be a cracked SMT capacitor or resistor.
AFAIK, the amplifier in the P!g is no longer in production, it was phased out a while ago (FWIW, it was codenamed Autobahn). You do seem them pop up on eBay, etc and you can still get one from Porsche parts (although you will likely need to have its firmware updated by the Porsche dealer...very simple procedure).
It is the 'connector' that the 2 plastic optical fibers (usually clad in orange) plug into on any MOST device.
You need to have some experience in electronics soldering in order to replace it....and of course you need a new FOT.
There is no guarantee that is your problem, since there are other things that could be causing it, like a cold solder joint on any of the IC's involved in the digital audio path (and there are many).
It could be a cracked SMT capacitor or resistor.
AFAIK, the amplifier in the P!g is no longer in production, it was phased out a while ago (FWIW, it was codenamed Autobahn). You do seem them pop up on eBay, etc and you can still get one from Porsche parts (although you will likely need to have its firmware updated by the Porsche dealer...very simple procedure).
01-15-2011, 05:19 PM
#17
Track Day
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Over the past two months I have experienced the zapping, the can't find cd/amp error, then no problems at all then no power, then all fine again. Since following this thread PCM is no powers or not working at all. I got a new amp and swapped it out today. CD is working and amp should work.... Buy PCM still does not turn on. I thought I would have fixed the problem with the amp..... Has anyone had success with a proper diagnosis and fix for these symptoms? I have a 2004 cayenne turbo.
By the way.. I also figured out how to remove the right hand luggage compartment panels to get o the amp. Not as hard as I thought it would be. I'll try to post directions in case someone needs them.
By the way.. I also figured out how to remove the right hand luggage compartment panels to get o the amp. Not as hard as I thought it would be. I'll try to post directions in case someone needs them.
04-12-2011, 07:04 PM
#18
Me Too- PCM Failure
Sounds like I have the same issue. Durametric is on the way, and I signed up for unlimited questions with a Porsche tech online. I'm going to tackle this issue during spring break. Can anyone create a PCM inspection checklist?
It sounds like some people blame the screen, others the MOST cable, some the amp.
With my case, my steering wheel controls don't work (both tiptronic and radio) - however the tiptronic works at the gear shift. On the rare occasion that the PCM kicks on, are your steering wheel controls working?
I have tried the "key" reset, holding 1,4,8 on the radio, pulling the fuse, and nothing has worked.
When the radio does work, it generally turns on after 20 min of driving. Will work until I turn off the truck, and then it will work until it sits and gets cold again.
Sometimes the radio will stay on even when the truck is off, keys are out, and the door is shut with the alarm on. I have to pull the fuse in that case.
So, here is my history. I will post my durametric results, and the conversation I have with the Porsche tech.
If anyone has a suggestion I should try, I'll be more than happy to give it a go.
It sounds like some people blame the screen, others the MOST cable, some the amp.
With my case, my steering wheel controls don't work (both tiptronic and radio) - however the tiptronic works at the gear shift. On the rare occasion that the PCM kicks on, are your steering wheel controls working?
I have tried the "key" reset, holding 1,4,8 on the radio, pulling the fuse, and nothing has worked.
When the radio does work, it generally turns on after 20 min of driving. Will work until I turn off the truck, and then it will work until it sits and gets cold again.
Sometimes the radio will stay on even when the truck is off, keys are out, and the door is shut with the alarm on. I have to pull the fuse in that case.
So, here is my history. I will post my durametric results, and the conversation I have with the Porsche tech.
If anyone has a suggestion I should try, I'll be more than happy to give it a go.
05-10-2011, 11:01 PM
#19
Intermediate
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I believe that Porsche is having serious problems with the PCM and, for financial reasons, management are doing their best to conceal it.
I originally posted my PCM problem as "Spilled Coffee=$4,000 repair?" in response to a thread complaining of the cup holder placement. My 2006 Carrera S PCM began acting erratically several months ago, on and off with "system error,amplifier,navigation unavailable". My dealership described it as resulting from spilled liquid on the facing. The service manager made it clear that this was common because of the driver side cup holder's placement (immediately over the PCM) insured any spillage would drip in and cause damage. He showed me the service bulletin that is Porsche's policy.
The problem is compounded by the fact that the PCM is made by Becker, not Porsche, so dealership can't even work on it. All they can do is replace unit, send it to Porsche who will send it to Becker, who will open it and, if any evidence of liquid (e.g. coffee stain) Becker will charge back to Porsche who will charge back to service manager. This is big money between 2 big companies.
Becker has a good point in that Porsche could have designed or specified a spillage-resistance from Becker but Porsche designed the cup holder to be right over PCM so should have or should redesign (or at least warn the consumer). The problem is Porsche will NOT warranty the repair despite the direct relationship between the negligent design and the damage. This is absolutely non-negotiable with them. I spoke to Porsche customer care, who promised to "look into it" and then simply sent me a denial of claim letter with no explanations and now will not return my phone calls.
My lawyer tells me I should pursue this matter.
I originally posted my PCM problem as "Spilled Coffee=$4,000 repair?" in response to a thread complaining of the cup holder placement. My 2006 Carrera S PCM began acting erratically several months ago, on and off with "system error,amplifier,navigation unavailable". My dealership described it as resulting from spilled liquid on the facing. The service manager made it clear that this was common because of the driver side cup holder's placement (immediately over the PCM) insured any spillage would drip in and cause damage. He showed me the service bulletin that is Porsche's policy.
The problem is compounded by the fact that the PCM is made by Becker, not Porsche, so dealership can't even work on it. All they can do is replace unit, send it to Porsche who will send it to Becker, who will open it and, if any evidence of liquid (e.g. coffee stain) Becker will charge back to Porsche who will charge back to service manager. This is big money between 2 big companies.
Becker has a good point in that Porsche could have designed or specified a spillage-resistance from Becker but Porsche designed the cup holder to be right over PCM so should have or should redesign (or at least warn the consumer). The problem is Porsche will NOT warranty the repair despite the direct relationship between the negligent design and the damage. This is absolutely non-negotiable with them. I spoke to Porsche customer care, who promised to "look into it" and then simply sent me a denial of claim letter with no explanations and now will not return my phone calls.
My lawyer tells me I should pursue this matter.
