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Porsche Club GB

Strange PCM1 behaviour

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17 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHStrange PCM1 behaviour

Leading reported evidence

Check fuse

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

I have checked the fuse for the PCM and it seems fine.

Strange PCM1 behaviour
Frequently discussed work

Check done

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

If you get a diagnostic check done, it should tell you what the fault is with the system.

Strange PCM1 behaviour
Read full discussion summary

Leading evidence: 'Check fuse' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check done' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

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1 matching discussions · 17 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Disconnect during the

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

Now the PCM unit refuses to switch on (the battery was disconnected during the repair.

Strange PCM1 behaviour

Install avic

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Last time I fitted an AVIC to my C2 I had to make up a filler piece at the top.

Strange PCM1 behaviour

Check done

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

If you get a diagnostic check done, it should tell you what the fault is with the system.

Strange PCM1 behaviour

Replace some of the things you don't have access

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

It's really handy for changing some of the things you don't have access to with the normal interface.

Strange PCM1 behaviour
Frequently discussed actions (9)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Check done

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

If you get a diagnostic check done, it should tell you what the fault is with the system.

Strange PCM1 behaviour

Check fuse

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

I have checked the fuse for the PCM and it seems fine.

Strange PCM1 behaviour

Disconnect during the

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster

Now the PCM unit refuses to switch on (the battery was disconnected during the repair.

Strange PCM1 behaviour

Install avic

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Last time I fitted an AVIC to my C2 I had to make up a filler piece at the top.

Strange PCM1 behaviour

Replace some of the things you don't have access

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

It's really handy for changing some of the things you don't have access to with the normal interface.

Strange PCM1 behaviour

Replace too

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

Also, I believe the majority of 'Porsche' speakers are 2 ohm, so they might need replacing too.

Strange PCM1 behaviour

Reset command in the computer

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Is there a reset command in the computer that the OPC forgot to issue when they did their stuff?

Strange PCM1 behaviour

Reset computer

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Just wish OPC had done this when they reset the Computer after the air bag was disconnected.

Strange PCM1 behaviour

Reset when it was plugged back in

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

As part of this work the door airbag was disconnected and the car sent to OPC to have the computer reset when it was plugged back in.

Strange PCM1 behaviour
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

17 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Porsche Club GB: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261027T154520Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Just had my 996 C4 cab in for some body repairs. As part of this work the door airbag was disconnected and the car sent to OPC to have the computer reset when it was plugged back in. Now the PCM unit refuses to switch on (the battery was disconnected during the repair. However, the PCM wont even switch on and ask for the security code. Which I'd expect) . The nav optical drive will spit out the cd so there is power to it and the PCM unit buttons illuminate (along with the rest of the dash) when I put the side lights on. I have checked the fuse for the PCM and it seems fine. Very fustrating Is there a reset command in the computer that the OPC forgot to issue when they did their stuff? Your collective wisdom gratefully received.

POST 2 / ORIGINAL POSTEROriginal post

Looking on the Internets I have discovered something called PCM lock-out mode???? Which can occur when the battery goes flat (the battery did go flat in my case). You need to take the car and your code cards for PCM+Nav to OPC to have them reset it? as in this mode the display does not function..i.e it wont prompt you to enter the codes yourself. Why? is this a typical Germanic security measure?...and another opportunity to part me with my cash ..`I guess I'd feel differently if it had been stolen. Just wish OPC had done this when they reset the Computer after the air bag was disconnected.

POST 3Original post

Lock-out mode should only occur after the security code has been entered 3 times incorrectly. After 10 minutes it should wake up and ask for the code again. This time increases if the incorrect code is entered repeatedly. It sounds like it might be that your unit has gone into transit (energy saving) mode, which is the state that it is in when it leaves the factory. If this is the case, you need to get it 'woken up' by someone with a Porsche System Tester (OPC or indy). Where are you located? If you are near me (Maidenhead, Berks) I could help.

POST 4 / ORIGINAL POSTEROriginal post

So after much trying this afternoon...the PCM has been shipped off for further investigation. Turns out that the fuse on the back is ok.....but maybe the power supply is fried :-( Which got me thinking...worst case scenario I need a new one....mucho cherching!...so what would be a suitable alternative (i dont have a MOST car or Bose but do have the Nav and phone features on my PCM...and a Dension ipod cradle). Are there 2din head units that have all these features?....can you get a replacement surround trim that will fit such a replacement? (I dont fancy having a big gaping hole in the dash.) will the wiring need hacking around with or is it plug and play?

POST 5Original post

If you get a diagnostic check done, it should tell you what the fault is with the system. I've just bought a Pioneer AVIC F900BT 2-din system for mine - another project for the Christmas holidays. Bluetooth, Nav, DVD, iPod, camera database, and more, all in one:

POST 6Original post

wow that looks a nice bit of kit ! - i have to ask santa to bring one perhaps !! [ ] is it touch screen , that looks to be way forward now . enjoy your new toy ! regards

POST 7 / ORIGINAL POSTEROriginal post

That does indeed look impressive.....Will it be plug and play? ...can you get adaptors for the wiring harness or do the plugs just fit straight in?.....What are your thought regadding the trim fitting?

POST 8Original post

Chris - Yes, it is touchscreen. I miss the one I had in my C2 so much, I decided to fit one to the Turbo. Robin - Until I get it to bits, I won't know for sure, but the main connections are standard DIN connectors, so it should be OK. I've just got to sort out the speed signal wire, which should be in the radio power plug, and the handbrake wire, which may or may not exist. There is a USB cable to connect the iPod or USB stick, and I want to route that to the centre console storage bin. The microphone and GPS antenna plug in the back of the unit, and I'm not connectiing any of the video cables, so I'm hoping it will be straightforward. The snag is that it has a highly complicated Kenwood Stereo/Satnav/TV/DVD unit with separate control boxes and a single-DIN head unit and flip-out monitor. Alongside that, there's a separate Bluetooth kit, and camera detector. (Offers anyone?) I expect it will be like spaghetti junction, and take me longer to strip out than fit the new one.. PCM is slightly taller than 2-DIN, and I've bought a fascia surround from a guy in the US. Last time I fitted an AVIC to my C2 I had to make up a filler piece at the top.

POST 9 / ORIGINAL POSTEROriginal post

I do hope you find success with your install...and await your findings In the meantime I'll keep my fingers crossed over Christmas and hope the PCM comes back in working order. Good Luck R

POST 10Original post

What a struggle that was! It took me all Boxing Day, and half of Saturday. Most of Friday was taken up removing all the Kenwood wiring, the Sony Ericsson bluetooth kit, and my Origin b2 camera detector. Then I had to convert all the wiring back to standard DIN connectors, as they had been cut to pieces by the "professionals". It was a real dog's breakfast before I started, and I am really pleased to have got rid of all the rubbish and tidy up the wiring loom. Before (without the Origin b2)​ This is what I removed​ The new installation​ It's taken me quite a while to configure it, install the camera database, update the software and generally set it up how I wanted, but it's been well worth the effort. It looks great, sounds great, and has tidied up the dash no end. So far, I'm a very happy bunny.

POST 11Original post

Looks great Richard. That may just make me reconsider buying a Turbo without PCM.

POST 12 / ORIGINAL POSTEROriginal post

Great pictures. Can I ask where you obtained the fascia from? And perhaps more importantly where you got the storage tray from below the main unit?...I'll potentially be removing the nav cd-rom drive and will need something in its place.

POST 13Original post

The trim came from http://stores.ebay.co.uk/Euromotorspeed . In fact, I bought the complete fitting kit, which was a waste of time, because I didn't use most of it. The cubby came from Porsche, part number 996.552.253.01.01C. £20.42, less discount, plus VAT. Since fitting the unit, I've been doing a lot of tinkering with it. In fact, the operating system is Windows CE, and you can boot it to Windows. It's really handy for changing some of the things you don't have access to with the normal interface. For example, the speed camera warning sound was a barking dog! Also, I couldn't transfer my phone contacts in one go (had to transfer them individually, due to a limitation on my phone). There is a db file on the AVIC that I can copy to the SD card, edit on my PC, and transfer back to the AVIC. So far, I'm really impressed.

POST 14Original post

Richard am I correct in thinking your new set up, which looks the mutts by the way, can't be achieved on my later 04 car with the MOST sysyem Ashley

POST 15Original post

It can be done, but you have to bypass the MOST system. Depending on what you have (CD23/PCM/CDC/Bose etc) you have to take out components of the system. Also, I believe the majority of 'Porsche' speakers are 2 ohm, so they might need replacing too. The more basic your system is, the easier it would be to fit the Pioneer (or similar system).

POST 16Original post

CDR23/upgraded amp and CDC, im probably going to get the speakers upgraded as per the Jon Mitchell speaker upgrades in 996 coupe thread when he re opens on the 22nd but seeing your install is making me reconsider whether to go the whole hog[8|]

POST 17 / ORIGINAL POSTEROriginal post

OK...so we are all good to go....and the culprit?...the info link fuse on the main fuse board.So nothing wrong with the PCM unit afterall.

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