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Headlight Internal Wire Harness Deteriorating

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Has anyone seen this before?


I have a 2006 Cayenne S.  Had left cornering light warning.  Went to replace the bulb and found the wires inside the headlight assembly had deteriorated.  The insulation was crumbling on most of the wires inside the headlight housing.


I had noticed flickering for the last couple of weeks.  Could this have been the root cause of the problem?


See attached pictures.


Any suggestions as to how to go about fixing this?


Have not found this harness available (only the one on the outside, or the one for the headlight).










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Cut off two of the spade connectors to the cornering light and the ground for the light and used shrink tubing.  Replaced the ends.  Just taped the others until I can come up with a better solution.


Lenses are beginning to yellow again.  Polished about a year ago.  May just have to break down and spend the money on new lights.


Anybody have a deal on them?



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  • Moderators

It looks like an already occurred shortcoming on some MY 964 alternator/engine wiring, these are then replaced with a factory recal. Despite the many fuses, it remains a fire hazard to me. Those with this problem could be related, to an OPC or their respective importer, the car checked and make a complaint, such thing have nothing to do with any warranty period given their action on the much older 964 a few years ago, at least this is my view on this matter. "If you do not shoot, you always miss the target" people say over here.

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  • 7 months later...

It is the insulation on the headlight wiring!!! 


I have been dealing with headlight issues for nearly two years ... dipped beam, light flickering, corning lights going out, and the list goes on.  I've replaced the head light gaskets, replaced many bulbs, worked on the contacts, and more.  I have continued to believe it was issues with the contacts and/or vibration in the light assembly causing the problems. 


Recently, however, when getting ready to replace another bulb I found the insulation on the wiring crumbling in my fingers.  This was inside the my LEFT headlamp housing.  I wrapped some electrical tape around it and it has continued to work well. 


I then lost most of the working lights in my RIGHT headlamp ... not at once, but over a week or so.  I opened up the RIGHT headlamp expecting to see the same issue found in my LEFT headlamp.  But, while there was some deterioration, it was not enough to impact all the lights that were out.  I then accessed the wiring harness behind the assembly only to find that by just pulling it, the insulation started falling apart in my hands.   I taped up all the wiring and all bulbs are working, and no flickering!  (The other headlamp still has a slight flickering ... probably the same issue.) 


I am now convinced all the problems from day one are related to the deteriorating insulation, thus causing the wiring to arc and causing these intermittent problems.  I will be replacing the harness on both headlamps. 


My guess is that these issues go well beyond the wiring inside the head lamps and wiring harnesses, and I will find problems with the wiring insulation throughout the vehicle.  My experience is that the wiring insulation should have a much much longer life than I am seeing here.  I've dealt with wiring issues on vehicles / boats much older than my 2006 -- and it was never the insulation.  I can only think the wiring insulation on the Porsche is a low grade material and that is why it is breaking down so early in its life.


I'd like to hear if there have been other wiring insulation problems found for issues other than the headlights.  It could explain other problems as they develop.


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  • 1 year later...

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