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Sooo.. first of all.. hi to everyone. I know this is my first post.. but I have been reading you guys for a few days now.. so I already feel at home¬†ūüėÖ¬†


Recently I became a happy owner of a porche.. I say happy even though I'm facing some dificulties on the way to registering the car. I knew car has some bugs but I got it at a grat price.. and  armed myself with patience to solve them.


First I replaced the flexible exhaust tubings because they were too leaky.. then I went to take care of the code that reported a faulty heater of the o2 sensor.. b1s1.. so I replaced the o2 sensor... and all seems to be fine for now even though I got the same code again and deleted it.. didnt come back yet.. this might be a clue for the next chapter..


So then I went to tackle the 4x4 psm failure when starting up the car.. Reading and reading watching youtube I learned that this occuered to someone when the battery was weak and dropping voltage bellow 8v at cranking the engine.. all happy I need only a new battery I went to measure voltages.. and on the emergency jump start connectors I read 15.5v at rest and lowest 13v cranking.. I have two batteries.. 


Honestly was a bit disappointed I was getting high readings.. because this means the batery is not the problem? Or could one of them still be the issue?


Could this cause o2 heater code to have reapiared? Maybe my old o2 sensor was good and this electrical thing is causing the o2 heater to fail just like psm and 4x4 is failing at startup. 


Codes I m getting now are 00470 and 00459.


00459 is because I unplugged the radio/screen.. I think.. could this be causing some issues? ( Sorry noob) says.. control module front.. no communication


And for 00470 

00470 - Combination comfort Databus in Single Wire: Open Circuit

Possible Symptoms

  • Data Bus Comfort working in Single-Wire Mode

Possible Causes

  • Wiring/Connectors from/to Control Modules
  • Control Module in CAN Data Bus Comfort faulty

Possible Solutions

  • Check Measuring Value Blocks (MVB)
  • Check Wiring/Connectors from/to Control Modules




Any help would be greatly appreciated..  I humbly beg for some compassion and guidance towards a solution.. 

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Ohh sorry.. When I saw my post.. I got afraid noone will read it¬†ūüėā¬†


Ohh.. if its a clue.. when I shut off the car 9/10 times I cant pull the key out unless I turn key right again and turn back.. then the key comes out.. 

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  • Admin

Fault code 0470
CAN comfort in single-wire operation

This fault was detected by the 'rear convenience system' control unit.


Possible causes of fault
‚ÄĘ Open circuit in CAN comfort (high)
‚ÄĘ Open circuit in CAN comfort (low)


Visual inspection: In the next troubleshooting section, please check first that the affected pins on the rear convenience system control unit plug connection are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and proper contact. Repair damaged or corroded
pins if possible, otherwise replace affected pins. Repair or replace damaged wires.


Sporadic faults: In the event of faults that occur sporadically, the wiring positions that are linked to moving parts on and in the vehicle must be checked for each system. Various statuses that can cause faults must be simulated with the help of the wiring diagram.


  • Thanks 1
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Thank you so much Loren for giving me something to read ūüôā letters give hope in more clues to fixing this.. I just wish I knew where this convinience unit is.. is it next to the fuse box on the passenger side? Plastic needs to be opened? Or next to fuses under the hood?

I apologize for such questions.. but I only had the car for a while.. actually feel happy to learn about it so much.. even if it is for troubleshooting reasons. I plan to do as much as I can on the car alone.


(Because of finances.. and the fact that I didnt run into a shop yet that was capable in actually troubleshooting the problem. They lean towards.. replace now.. ask questions later. Who could afford such a sloppy work.. paying thousands for random parts when a problem could be a wire makes no sense)


Sorry.. a bit of a side rant)

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Posted (edited)

Ok! Great progress! So, my volt meter was off.. and indeed front battery was bad.. and in addition to that I discovered with a friends help the battery in the back was still very good, but wired wrongly.. without the relay.. so the front bad battery was draining the good one.. 2amps.. at all times.. so we hooked the batteries correctly over the relay, and I went and replaced the front one with a new 100Ah 850a battery. All psm and 4x4 failiures thank God went away.. now I get only a p00130 code and I suspect it's a corroded wire for b1s1 o2 sensor. Since it comes back after 20 mins.. after I delete the code. I plan to replace the wire since the o2 sensor is new hooked to the old wire that was there. 


I plan to do these steps found here 



Hope this solves the issue, any additional imput appreciated. I hope all this text I wrote at least helps someone else one day ūüôā

Edited by HeavenWillBe El
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Posted (edited)

Replaced the wire going from sensor to connector. First ride dtc 130 came up.. deleted it.. second ride no dtc found..


So its not the wire.. help please.. is it spark plugs?


I can smell the fuel and my mpg is worse than normal.. but no dtc except for 130 every now and then



Edited by HeavenWillBe El
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Replaced sparkplugs today.. old ones were crap.. car runs like a dream now.. mpg went down drastically.. had dtc p30 appear deleted it and will see if it reappears.. there.. thats the progress..¬† if anyones reading ūüôā

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Good news is I managed to get the car registered today.. passed the emissions and all.. later on p030. Returned. I still intend to fix it.. just running out of ideas.. maybe I ll switch the ignition coils from left side to rite and see if b2s1 comes as faulty.. then I could pinpoint if the left side coils are the issue to throw off b1s1.. any more ideas if this fails?

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  • 1 month later...
On 6/9/2021 at 12:29 PM, HeavenWillBe El said:

Good news is I managed to get the car registered today.. passed the emissions and all.. later on p030. Returned. I still intend to fix it.. just running out of ideas.. maybe I ll switch the ignition coils from left side to rite and see if b2s1 comes as faulty.. then I could pinpoint if the left side coils are the issue to throw off b1s1.. any more ideas if this fails?

 Did you check the wiring going to the coils?  High temperature makes them really brittle 

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