Fault code disabling air compressor - reset?

[Papagut]

Hi,

I have been having some problems with the air compressor for the ride height adjustment in my 05 Cayenne Turbo, so I removed it, disassembled it, cleaned it up (it was filthy and corroded inside), then reassembled it and put it back in the car. I bench tested the compressor and it worked like a charm, so I know it is working well now. However, after reinstalling it, it refuses to charge the system. I did run the car while it was removed, so I am assuming that it believes it is not present and has disabled the system entirely.

Is there a way to clear or reset the error system so that it is reenabled (without visiting a shop to clear the error codes)?

Thanks,

Mark

[mudman2]

How do you know it was the compressor causing the problem ? it may be something else.

[Loren]

Did you check the ride height control fuses?

[wvicary]

What was the orignal problem you were having that pointed to the compressor? On a side note - VW offers a repair kit for the compressors.

[Papagut]

Thanks for that excellent tip - I had no idea VW offered a repair kit. That could definitely come in handy.

So, originally, I had a problem with the system charging, and traced it to an air line t-junction that had came loose under the rear seats. Once that was fixed, and over time, I thought that the compressor was beginning to sound more loud and laboured. A shop where I do some service mentioned that he had seen an older compressor that had accumulated a surprising amount dirt and water, so I took it out and disassembled it inspect it and clean the components - it was clearly dirty and had a fair amount of residue buildup. I replaced all the seals and lubricated it, and it worked beautifully - nice and quiet.

However, upon reinstalling it in the car, it will not engage. My first check was the fuses, and I ended up checking them all as I know some systems can influence others (including under the hood). All are fine. As a double check I bench tested it again, and it works perfectly.

So, that is what led me to believe that perhaps a fault code was registered since I started the car while the compressor was not present that had disabled the system.

Let me know what you think, or if you have any more questions.

Mark

[Loren]

Swap out the relay?

[Papagut]

No, good suggestion.

Under the dash drivers side I assume - can you identify the relay that runs the power for the compressor for me? Or is there an resource that I can use to identify it for myself?

Mark

[Loren]

[Papagut]

Thanks, I will give this a test and get back to you with the results.

Mark

[wvicary]

You sound like a fellow that tries to do his own repairs and I believe one of the best tools you can have at your side when working on Porsche is Durametric software. I'm not 100% sure but I think it can read ride control faults. Check out the their website or contact them to verify. These vehicles are complicated and often without at least fault codes it's nothing but a guessing game.

[Papagut]

Thanks, another good suggestion, I always thought that it was very costly, but I see now that you can get started for under $300. I told my wife what I want for my next birthday.

As for the compressor, it is solved. Here is what I did:

I exposed the relay in question and saw that it did trip when the car was started. Then I tested the circuit itself, and it had no power. That is when I remembered that there are a few additional fuses under the seat beside the battery. And that is it - the 40 amp fuse under the seat was blown. Replaced it and the compressor charges the system immediately and I am back to normal.

So Loren, I suppose I should have been more thorough when checking fuses at the beginning.

Anyhow, I am very pleased to have it solved, and as always, greatly appreciate the excellent suggestions and support of the community.

Thanks,

Mark

[wvicary]

Glad you got it sorted and thanks for getting back to us with the result.