Major issues at the track this past weekend - PDK
11-22-2022, 12:35 PM
#1
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Major issues at the track this past weekend - PDK
2009 Cayman S PDK and Sportchrono
Hello all! I'm hoping the 987 brain-trust might have some knowledge on a problem I ran into at VIR last weekend. Wild speculation not unwelcome.
My car ran wonderfully all day on Saturday, being new to me, I started out first session in "normal" mode, second session in "sport", third session in "sport plus". Considering the high revs in sport plus, I determined that starting out in "Sport" and switching to "Sport Plus" once I attained higher speeds was the better course, no sense in doing 35mph at 7000 rpms down pit lane. Anyway, 4 great runs on Saturday.
On Sunday, I ran in a faster run group and had several of my best lap times ever at VIR, I was absolutely ecstatic. On my last 1/2 lap before checker (VIR throws checker before back straight), suddenly my car seems to lose power, revs went independent of speed and I'd alternate between power and no power. Looking back at the video, it seems like suddenly my clutches were not engaging or slipping really badly. It caught again, then acted up again a few turns later. selected gear was all over the place, I think because the computers could not longer figure out what gear it was supposed to be in. I cooled down, pitted and pulled codes with a Foxwell.Here is a list of all P codes that I recorded after this issue first started appearing. Unfortunately, I did not record subsequent errors as they popped up, but each time I cleared them, the car would run ok for about 5 minutes before acting up.
P18B4 – Software Error
P1990 – Positive engine torque intervention not possible
P1991 – Engine torque intervention not possible
C152 – Communication PSM control unit (drive)
C150 – Communication DME control unit (drive)
5400 – Fault Sport Mode
8005 – Terminal S – (upper limit value exceeded)
P1552 – function monitoring: CU fault group a
P1629 – Fault manual transmission control module
I cleared the codes and went for a test drive, they came back within a mile and the car started acting up, same symptoms. Since the car seemed to be running ok in "manual" mode, I packed up and attempted to limp home. Within about 5 miles, manual mode wasn't working, at a stop sign turning onto a busy state road, I wisely decided to wait for the oncoming tractor trailer barreling at me at 70mph. I had absolutely no clutch engagement at that point and pulled off the road. No reverse, no forward, check engine light. I turned the car off, and checked codes. There were a few extra ones this time including a temperature warning, which I regret not taking a photo of. I waited a few minutes and turned it back on, started driving properly again (still with check engine - bring to workshop) on display. I managed to make it back to the paddock, reset the codes once again and drove it up to Quantum Speedwerks, which is on the VIR grounds. No codes. Mechanic took it for a spin, couldn't throw any codes. Pulled it onto their alignment rack to do an inspection, still all clear. Went to reverse it off the lift, no engagement, codes. The diagnosis guide suggests a reset of codes and a reprogramming which they attempted with an Altell, then with a PIWIS3, the codes now won't clear and no reprogramming is possible w/o clearing those codes. I believe their plan was to perform a clutch recalibration. If anyone has any previous experience with this, or specialized knowledge of PDK, I'd appreciate your help.
The P18B4 seems to indicate either a CAN bus fault or faulty PDK control unit. The shop was reading a bunch of CAN bus errors so I'm hoping that I have a software or electrical problem. My voltage when I brought the car into the shop was 80% charge, they charged the battery and I'm going to ask them to check the charging system and battery but I would think that Porsche would have a Pcode for that, since they have a code for everything else including floppy door handles. I'm continuing to search on all of the codes thrown to see if I can find a pattern, but I figured I'd ask here as well. Thanks! Marc
Hello all! I'm hoping the 987 brain-trust might have some knowledge on a problem I ran into at VIR last weekend. Wild speculation not unwelcome.
My car ran wonderfully all day on Saturday, being new to me, I started out first session in "normal" mode, second session in "sport", third session in "sport plus". Considering the high revs in sport plus, I determined that starting out in "Sport" and switching to "Sport Plus" once I attained higher speeds was the better course, no sense in doing 35mph at 7000 rpms down pit lane. Anyway, 4 great runs on Saturday.
On Sunday, I ran in a faster run group and had several of my best lap times ever at VIR, I was absolutely ecstatic. On my last 1/2 lap before checker (VIR throws checker before back straight), suddenly my car seems to lose power, revs went independent of speed and I'd alternate between power and no power. Looking back at the video, it seems like suddenly my clutches were not engaging or slipping really badly. It caught again, then acted up again a few turns later. selected gear was all over the place, I think because the computers could not longer figure out what gear it was supposed to be in. I cooled down, pitted and pulled codes with a Foxwell.Here is a list of all P codes that I recorded after this issue first started appearing. Unfortunately, I did not record subsequent errors as they popped up, but each time I cleared them, the car would run ok for about 5 minutes before acting up.
P18B4 – Software Error
P1990 – Positive engine torque intervention not possible
P1991 – Engine torque intervention not possible
C152 – Communication PSM control unit (drive)
C150 – Communication DME control unit (drive)
5400 – Fault Sport Mode
8005 – Terminal S – (upper limit value exceeded)
P1552 – function monitoring: CU fault group a
P1629 – Fault manual transmission control module
I cleared the codes and went for a test drive, they came back within a mile and the car started acting up, same symptoms. Since the car seemed to be running ok in "manual" mode, I packed up and attempted to limp home. Within about 5 miles, manual mode wasn't working, at a stop sign turning onto a busy state road, I wisely decided to wait for the oncoming tractor trailer barreling at me at 70mph. I had absolutely no clutch engagement at that point and pulled off the road. No reverse, no forward, check engine light. I turned the car off, and checked codes. There were a few extra ones this time including a temperature warning, which I regret not taking a photo of. I waited a few minutes and turned it back on, started driving properly again (still with check engine - bring to workshop) on display. I managed to make it back to the paddock, reset the codes once again and drove it up to Quantum Speedwerks, which is on the VIR grounds. No codes. Mechanic took it for a spin, couldn't throw any codes. Pulled it onto their alignment rack to do an inspection, still all clear. Went to reverse it off the lift, no engagement, codes. The diagnosis guide suggests a reset of codes and a reprogramming which they attempted with an Altell, then with a PIWIS3, the codes now won't clear and no reprogramming is possible w/o clearing those codes. I believe their plan was to perform a clutch recalibration. If anyone has any previous experience with this, or specialized knowledge of PDK, I'd appreciate your help.
The P18B4 seems to indicate either a CAN bus fault or faulty PDK control unit. The shop was reading a bunch of CAN bus errors so I'm hoping that I have a software or electrical problem. My voltage when I brought the car into the shop was 80% charge, they charged the battery and I'm going to ask them to check the charging system and battery but I would think that Porsche would have a Pcode for that, since they have a code for everything else including floppy door handles. I'm continuing to search on all of the codes thrown to see if I can find a pattern, but I figured I'd ask here as well. Thanks! Marc
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12-18-2022, 12:58 PM
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Thread Starter
Well, two Thursdays ago, I had my Cayman flat-bedded up to my local Dealership, Checkered Flag Porsche in VB. I went full boyscout, told them exactly what happened at the track, gave them my research notes and asked them to reprogram both computers, and see if the vehicle data was still present. From past experiences with other dealers and shops, I was expecting pushback about "we'll do our own diagnostics" and we can't program a second-hand computer, etc. I was pleasantly surprised, they put me through to the service manager who is an HPDE instructor and we ended up chatting for about 20 minutes about Porsches, VIR, and performance upgrades. He told me "no problem", they'd take a look.
They were able to reprogram both computers, and performed a PDK clutch calibration, my Cayman is running perfectly now. This is EXACTLY the work I was trying to perform using my "PIWIS 3" when it failed miserably. The total cost was just under $600, which I thought was fair for a dealership repair, hell, the independent out at VIR charged me nearly $800 and made it worse.
I didn't have a chance to try the PIWIS II to see if it fared any better, and I don't want to risk wiping the programming off either of my PDK computers just to test it. Before track season, I may attempt to perform the "Replace PDK Controller" operation so I can swap in the replacement controller (Dealership left my factory issued unit in place), the "Read" function is now present, and executes on my original PDK controller, though I have absolutely NO IDEA *where* it is saving that data. I don't really trust the old controller as I still suspect the issue was due to an overheat, that is the only way I can see for a computer to just completely lose its programming:
P18B4 – Software Error
P1990 – Positive engine torque intervention not possible
P1991 – Engine torque intervention not possible
C152 – Communication PSM control unit (drive)
C150 – Communication DME control unit (drive)
5400 – Fault Sport Mode
8005 – Terminal S – (upper limit value exceeded)
P1552 – function monitoring: CU fault group a
P1629 – Fault manual transmission control module
Anyway, I seem to be the only person in the world who has experienced this particular issue so far. Hopefully this thread will prove valuable to someone in the future if this issue ever crops up again! Another factlet that might be useful, I forget the Option Code, but this car was one of the very earliest production 987.2's, the option code indicates that it was a Demo car, maybe a press car? The PDK controller was absolutely superseded during the 2009-2012 production, maybe there is something there. When I have a chance I'll grab the P/N and the Option code and append it to this thread. Again, for posterity at this point.
Happy to be back on the road! Thanks to everyone for their suggestions and help in resolving this issue!
They were able to reprogram both computers, and performed a PDK clutch calibration, my Cayman is running perfectly now. This is EXACTLY the work I was trying to perform using my "PIWIS 3" when it failed miserably. The total cost was just under $600, which I thought was fair for a dealership repair, hell, the independent out at VIR charged me nearly $800 and made it worse.
I didn't have a chance to try the PIWIS II to see if it fared any better, and I don't want to risk wiping the programming off either of my PDK computers just to test it. Before track season, I may attempt to perform the "Replace PDK Controller" operation so I can swap in the replacement controller (Dealership left my factory issued unit in place), the "Read" function is now present, and executes on my original PDK controller, though I have absolutely NO IDEA *where* it is saving that data. I don't really trust the old controller as I still suspect the issue was due to an overheat, that is the only way I can see for a computer to just completely lose its programming:
P18B4 – Software Error
P1990 – Positive engine torque intervention not possible
P1991 – Engine torque intervention not possible
C152 – Communication PSM control unit (drive)
C150 – Communication DME control unit (drive)
5400 – Fault Sport Mode
8005 – Terminal S – (upper limit value exceeded)
P1552 – function monitoring: CU fault group a
P1629 – Fault manual transmission control module
Anyway, I seem to be the only person in the world who has experienced this particular issue so far. Hopefully this thread will prove valuable to someone in the future if this issue ever crops up again! Another factlet that might be useful, I forget the Option Code, but this car was one of the very earliest production 987.2's, the option code indicates that it was a Demo car, maybe a press car? The PDK controller was absolutely superseded during the 2009-2012 production, maybe there is something there. When I have a chance I'll grab the P/N and the Option code and append it to this thread. Again, for posterity at this point.
Happy to be back on the road! Thanks to everyone for their suggestions and help in resolving this issue!
11-22-2022, 06:12 PM
#2
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My cayman R w/pdk did this only when I drove at night with lights on. It came with lithium antigravity battery that went dead after having sat for 6 weeks but I reconditioned it with a CTEK lithium battery tender/maintainer. Drove to work in the daytime fine, but when I drove it twice from work at night, it would go ~1 mile before the transmission started stuttering and car would shut off. The first time, the car was "DEAD" with the key being stuck inside the ignition for ~3 min before the car's electrical system came back on and the car restarted but came be driven for any distance. The second time, I used the "emergency power" keyfob that came with the anti-gravity battery to restart the car and make it back to the hospital parking lot before it almost died again when I used the window switch.
After the first time, I had reconditioned the battery and had my car flatbed to a local Porsche specialist show (The Porsche Specialist) and they found no fault/codes.
After this last time, I am going to change batteries then drive it back to the Porsche mechanic and have them check the charging system/alternator.
Hopefully, someone more familiar with the PDK can chime in and give us/confirm it is the battery.
After the first time, I had reconditioned the battery and had my car flatbed to a local Porsche specialist show (The Porsche Specialist) and they found no fault/codes.
After this last time, I am going to change batteries then drive it back to the Porsche mechanic and have them check the charging system/alternator.
Hopefully, someone more familiar with the PDK can chime in and give us/confirm it is the battery.
11-22-2022, 06:21 PM
#3
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Thread Starter
My cayman R w/pdk did this only when I drove at night with lights on. It came with lithium antigravity battery that went dead after having sat for 6 weeks but I reconditioned it with a CTEK lithium battery tender/maintainer. Drove to work in the daytime fine, but when I drove it twice from work at night, it would go ~1 mile before the transmission started stuttering and car would shut off. The first time, the car was "DEAD" with the key being stuck inside the ignition for ~3 min before the car's electrical system came back on and the car restarted but came be driven for any distance. The second time, I used the "emergency power" keyfob that came with the anti-gravity battery to restart the car and make it back to the hospital parking lot before it almost died again when I used the window switch.
After the first time, I had reconditioned the battery and had my car flatbed to a local Porsche specialist show (The Porsche Specialist) and they found no fault/codes.
After this last time, I am going to change batteries then drive it back to the Porsche mechanic and have them check the charging system/alternator.
Hopefully, someone more familiar with the PDK can chime in and give us/confirm it is the battery.
After the first time, I had reconditioned the battery and had my car flatbed to a local Porsche specialist show (The Porsche Specialist) and they found no fault/codes.
After this last time, I am going to change batteries then drive it back to the Porsche mechanic and have them check the charging system/alternator.
Hopefully, someone more familiar with the PDK can chime in and give us/confirm it is the battery.
Thanks for sharing your experience. Since the car is new to me, I don't know how old the battery is or whether it is in good condition. Wouldn't it be nice if it were just a battery issue! I was just on the phone arranging for shipping back to my house. I asked the shop to check the battery condition and gave them permission for a new battery if needed, but I think they are busy and a bit spooked doing anything further on this car. When I left it on Sunday there were multiple codes that would no longer clear, and I'm not even sure if it was starting. When I checked it into the shop, all the codes were clear and it drove in under its own power. I have a feeling the car didn't like whatever they did to it with the PIWIS.
11-24-2022, 06:41 PM
#4
Sorry to hear you had trouble at VIR. My issues started at WGI. The symptoms were different and the codes were different, but ultimately I suspect my issued started with a drained battery...which caused an electrical issue in the PDK. I drained the battery while doing a repair and then recharged it with a CTEK. When I started it up the first time I got a gear selection error. Coming down the front straight my PDK went into limp mode and locked in 3rd gear until I got it into the garage and parked. Then it wouldn't move at all. I thought it was the gear position sensor based on my errors, but a friend mentioned he had a similar situation when a wheel speed sensor was bad. Sure enough I had speed sensor errors stored. I cleared all the codes, did a calibration routine, and ultimate a full PDK clutch calibration. Since then I've had zero codes/errors and the PDK shifts smoother than ever. I've done another four track days with no issue.
So, I'd suggest you fully the battery and confirm your alternator is in good working order. Clear all the codes, and do the PDK calibration and/or the clutch calibration if you have a PIWIS. Hopefully you'll be in the clear.
So, I'd suggest you fully the battery and confirm your alternator is in good working order. Clear all the codes, and do the PDK calibration and/or the clutch calibration if you have a PIWIS. Hopefully you'll be in the clear.
11-24-2022, 07:11 PM
#5
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Thread Starter
Sorry to hear you had trouble at VIR. My issues started at WGI. The symptoms were different and the codes were different, but ultimately I suspect my issued started with a drained battery...which caused an electrical issue in the PDK. I drained the battery while doing a repair and then recharged it with a CTEK. When I started it up the first time I got a gear selection error. Coming down the front straight my PDK went into limp mode and locked in 3rd gear until I got it into the garage and parked. Then it wouldn't move at all. I thought it was the gear position sensor based on my errors, but a friend mentioned he had a similar situation when a wheel speed sensor was bad. Sure enough I had speed sensor errors stored. I cleared all the codes, did a calibration routine, and ultimate a full PDK clutch calibration. Since then I've had zero codes/errors and the PDK shifts smoother than ever. I've done another four track days with no issue.
So, I'd suggest you fully the battery and confirm your alternator is in good working order. Clear all the codes, and do the PDK calibration and/or the clutch calibration if you have a PIWIS. Hopefully you'll be in the clear.
So, I'd suggest you fully the battery and confirm your alternator is in good working order. Clear all the codes, and do the PDK calibration and/or the clutch calibration if you have a PIWIS. Hopefully you'll be in the clear.
LA Dismantlers has a used PDK controller on its way to me, $275 shipped. I compiled a list of the relevant flowcharts and Technical Service Bulletins, and found the PDK controller replacement procedure in my alldatadiy.com subscription. The biggest demon I'm facing right now is that the shop eventually produced codes that they could not clear, so that is where I'll start my diagnosis. The "3730 PDK Flowchart" appears to be my best friend.
I ordered a Brombacher aluminum (replaceable filter) PDK pan and a LN Bilt PDK oil cooler as well. My plan is to not only resolve this issue but flush the hydraulics and upgrade the cooler. I'm hoping to get one more track day in before winter sinks its teeth in. I'm way more optimistic than I was on Sunday thanks to great internet resources such as this forum, Planet-9, Pelican and others. I really appreciate you sharing your experiences. I'll continue updating this post as I (hopefully) figure this out.
Happy Thanksgiving everyone!
Marc
11-24-2022, 09:46 PM
#6
Rennlist Member
Pls.keep us up to date as things progress.
11-25-2022, 08:38 PM
#7
That clutch side cooler is annoying to install. Give yourself some time.
I wouldn’t buy any electronic parts until after the charge, clearing of codes, and calibration. I was certain I need med the $2000 position sensor and was already talking to shops.
Good luck
I wouldn’t buy any electronic parts until after the charge, clearing of codes, and calibration. I was certain I need med the $2000 position sensor and was already talking to shops.
Good luck
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11-29-2022, 12:11 AM
#8
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Thread Starter
Update: car finally arrived back to VB, won't shift into or out of gear w/o manual override.
- Won't start, says to put selector into P or N, neither of which are detected. Selector on dash indicates properly selected gear however.
- Brake switch appears to work as the display does indicate you need to hold the brake when starting, if I don't brake
Hooked up a PIWIS, many errors, most significantly (and supportive of my best case assumption of the control unit being dead) is:
PDK shows a serial number of 00000000000 during inventory
Porsche DoppelKupplug (PDK) - 10040: Control unit not programmed
Attempted to program - "Programming of the control unit has failed" - "Fault memory cannot be erased"
I tried disconnecting both harnesses to the PDK control unit and rerunning diagnostics with it disconnected to see if the diagnostics looked the same whether it was connected or not, it did not. W/o harnesses, the PDK line on the main diagnostics inventory remained grayed out as did A/C
I reconnected the harnesses to the PDK control unit and reran diagnostics again, looked pretty much the same, LOTS of communication errors especially:
DME
P1691 - Communication, transmission control unit (no signal)
P169A - Communication, transmission control unit (below limit value)
P1628 - CAN interface, sigs no communication (no signal)
PDK
no code - 10040: Control unit not programmed
PSM
4444 - Steering angle sensor not initialized (no fault symptom available) - I'VE SEEN THIS ONE MANY TIME AND CLEARED IT BY RECALIBRATION(???)
C151 - Communication Tiptronic control unit (drive) (No fault symptom available)
PAS
C151 - Communication Tiptronic control unit (drive) (exceeds limit value)
POSIP
C152 - Communication PSM control unit (drive) (no fault symptom available)
... many more, mostly related to communications with the instrument cluster, PCM and gateway
PDK Selector shows no faults, so its likely doing what its told by the other CUs.
- Won't start, says to put selector into P or N, neither of which are detected. Selector on dash indicates properly selected gear however.
- Brake switch appears to work as the display does indicate you need to hold the brake when starting, if I don't brake
Hooked up a PIWIS, many errors, most significantly (and supportive of my best case assumption of the control unit being dead) is:
PDK shows a serial number of 00000000000 during inventory
Porsche DoppelKupplug (PDK) - 10040: Control unit not programmed
Attempted to program - "Programming of the control unit has failed" - "Fault memory cannot be erased"
I tried disconnecting both harnesses to the PDK control unit and rerunning diagnostics with it disconnected to see if the diagnostics looked the same whether it was connected or not, it did not. W/o harnesses, the PDK line on the main diagnostics inventory remained grayed out as did A/C
I reconnected the harnesses to the PDK control unit and reran diagnostics again, looked pretty much the same, LOTS of communication errors especially:
DME
P1691 - Communication, transmission control unit (no signal)
P169A - Communication, transmission control unit (below limit value)
P1628 - CAN interface, sigs no communication (no signal)
PDK
no code - 10040: Control unit not programmed
PSM
4444 - Steering angle sensor not initialized (no fault symptom available) - I'VE SEEN THIS ONE MANY TIME AND CLEARED IT BY RECALIBRATION(???)
C151 - Communication Tiptronic control unit (drive) (No fault symptom available)
PAS
C151 - Communication Tiptronic control unit (drive) (exceeds limit value)
POSIP
C152 - Communication PSM control unit (drive) (no fault symptom available)
... many more, mostly related to communications with the instrument cluster, PCM and gateway
PDK Selector shows no faults, so its likely doing what its told by the other CUs.
11-29-2022, 12:23 AM
#9
Rennlist Member
Thread Starter
Oh, and does anyone have ANY clue as to why A/C seems to be tied so deeply into these cars? When I disconnected the PDK CU, A/C failed to detect as well. Also, I've heard that when programming things like sport mode, that the A/C configuration can cause issues.
11-29-2022, 09:02 AM
#11
I had to go to my stealer to change the amplifier, so it seems to me your PDK unit is fried :-/
11-29-2022, 11:57 AM
#12
Rennlist Member
Thread Starter
Just odd that the entire "A/C" option would be grayed out. I could see it throwing an error. I suspect you are right though, the transmission likely needs to know about the load and maybe keep revs higher to keep the engine in its load comfort zone. Thanks! Marc
11-29-2022, 11:59 AM
#13
Rennlist Member
Thread Starter
I tried to re-program my Bose amplifier on my 987.2 PDK with my Piwis 2. It failed, and after I had exactly the same faults (serial number 0000000000, control unit not programmed, programming has failed).
I had to go to my stealer to change the amplifier, so it seems to me your PDK unit is fried :-/
I had to go to my stealer to change the amplifier, so it seems to me your PDK unit is fried :-/
11-29-2022, 12:07 PM
#14
Rennlist Member
Thread Starter
Another symptom that I noticed last night, but I saw, and unwisely ignored previously...
When I connect the PIWIS 3 laptop and go into diagnostics, I get a battery low warning. The battery was a bit low at the dealership (83%) when I pulled it in, but they were able to charge it back up. I wonder if all of this may have been caused by a bad battery or an alternator issue. I'll address the possible battery issue before proceeding, I don't want to blank another controller. I strongly suspect that the shop I brought the car to may have tried to reprogram the controller and bricked it. From a hardware perspective, its possible that the EEPROM has given up the ghost and *any* attempt to program it would have bricked it so I'm not pointing fingers, but this is why I wanted the car back in my hands.
When I connect the PIWIS 3 laptop and go into diagnostics, I get a battery low warning. The battery was a bit low at the dealership (83%) when I pulled it in, but they were able to charge it back up. I wonder if all of this may have been caused by a bad battery or an alternator issue. I'll address the possible battery issue before proceeding, I don't want to blank another controller. I strongly suspect that the shop I brought the car to may have tried to reprogram the controller and bricked it. From a hardware perspective, its possible that the EEPROM has given up the ghost and *any* attempt to program it would have bricked it so I'm not pointing fingers, but this is why I wanted the car back in my hands.
11-30-2022, 01:54 PM
#15
Rennlist Member
Thread Starter
Update as of last night... I had left the PIWIS adapter plugged into the car overnight and the battery was dead yesterday morning. This does not seem like a high draw device, especially with no PIWIS actively engaging it, so I chose to put a new battery in. With a new, charged battery and a big honkin, fully-charged jump-box borrowed from my buddy connected to it, I still get the PIWIS "battery low" warning. I see two possibilities, either the after-market PIWIS adapter is missing the battery voltage detection functionality, or I have a problem with a whatever power-supply exists on this car to regulate 12V and (presuming) 5V power to the OBDC2. DC->DC conversion is not rocket science and seems unlikely, especially with symptoms other than the PIWIS. Can anyone else with a PIWIS confirm they also get a "low voltage" detection when using a PIWIS "clone"?
I have a DMM at my shop, my car is at home. I suppose I'll have to grab it and get an OBDC pinout and test the voltages at the connector. Sigh.
I have a DMM at my shop, my car is at home. I suppose I'll have to grab it and get an OBDC pinout and test the voltages at the connector. Sigh.