wwest

Let me introduce you to a purely BLOND PCNA factory representative!

I have a letter right here in hand dated September 11th, 2004 from Rick
Podorski, Western Regional Service Manager for PCNA, Porsche Cars North
America.

It is in response to my enquiry of September 1, 2004 regarding the status of
a firmware update fix for the climate control system in my 2001 Porsche C4.
The C4's climate control system often ("part of the system's normal
operation." R. Podorski) cools the windshield so severely on a hot and humid
day, or night, that the exterior surface of the windshield will fog over,
sometimes almost instantaneously.

I had noticed on a web forum that VW had issued a firmware update for
the Touareg SUV that corrected this very problem. So basically my question
was if VW has fixed the touareg climate control then the VW fix will
probably be applicable to the Cayenne and maybe my C4.

Here is a single sentence from my letter which will indicate just how well
we can expect a factory service representative to keep up on these things.

"Porsche Cars can appreciate the time you have spent researching this matter
with another manufacturer, but these are two different systems that cannot
be compared."

The VW Touareg and the Porsche Cayenne climate control systems CANNOT BE
COMPARED!

Hmmm...

Maybe someone should inform the workers and/or the buyers in the jointly
owned Porsche/VW factory where both are build using ~90% of the same
components.

Just as asian manufacturers primarily use NipponDenso, many european
manufacturers use Bosch as a resource for electrical and electronic designs and components.

I verified just last evening that an owner of a new BMW has exactly the same
complaint. His solution is to lay a towel over the windshield airflow defog/demist outlet ducts in the summertime to prevent the windshield outside temperature from declining to dewpoint.

LVDell

Typical isn't it? That is all they respnded with? No solution? No fix? No explanation? No nothing?

wwest

Like Toyota and Lexus on the engine hesitation symptom....

"part of the system's normal operation..." R. Podorski

Eric - Plug Guy

Please clarify: If the VW and Cayenne units are similar (we know they are), how do you draw the similarity to the C4 system? They are completely different.

However, I do agree that DSM's vary, and this guy probably knows a lot less about the car than most of us on these boards! Shame on them.

What happens when you hit the 'side vents only' button on your A/C? Do you still get fogging?

Fred R. C4S

FWIW

I'm in the "product support business" and likely to slam someone who provides poor support. Why do we conclude that the VW/Cayenne system is the same as that on a 996C4? Could it possible that they are somewhat different in system design?

In my business too many of our front line field service reps are only just out of the training program. This is just the first rung on the corporate service / support ladder.To really get an answer, you need to speak with someone in the design or development department. My company has an easy way for our dealers and service reps to do this. Unfortunately, Porsche does not.

Cheers,

wwest

Both made by Bosch, Both COOL the interior surface of the windshield on a hot and humid day when the system is in cooling mode. I should point out that the COLD airflow to the windshield seemingly only starts to flow once the temperature setpoint is nearly reached. If your setpoint is 71F then airflow to the windhsield will start when the cabin temperature has declined to ~75F.

Since all of these systems have, need, the exactly same functionality and use the same origin, Bosch, why wouldn't the same ECU firmware be used throughout?

I avoid the situation by trying to always remember to over-ride my system so cooling air only flows from the dash outlets, or for quick cooldown, dash and footwell outlets.