Question about 2003 Porsche Cayenne

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03 cayenne PCM does not switch on!

After removing the PCM head unit to reinstall the fibre optic leads,the unit would not restart! Fuses all good! 049 fault code extracted by scanner,(PCM uncommunicative/inoperative) does the unit need recoding?

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Came across this problem before. Check in the back of the vehicle where your amplifier is. Make sure there isn't any moisture on it. The rear washer lines maybe leaking and shorting the amplifier out. If this isn't the problem you may need to have the P.C.M. recalibrated, especially if you've added any upgrades. Good luck.

Posted on Dec 11, 2014


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Under the dash right above your left foot.

Posted on May 20, 2011

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SOURCE: hey guys i have a cayenne s 2006 my pcm unit is not responding to anything the only thing working is the volume can you tell me what to do

its went bad replace is all you can do.

Posted on Aug 04, 2012

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