[s-cars] HVAC code gurus please

[Tom Green]

Sorry, but you didn't find a guru here, Sam.  :-)
Since the codes you have are intermittent faults, it means the  
potentiometer on the
little motor (and the flap) didn't move as fast as the controls  
directed--sticky flap or the
little motor is getting tired, but only occasionally doesn't do the job.
It is a good idea to clear the codes and check after operating a  
while to see if they
return, especially these intermittent codes.
Audifans and the 12v site Vincent offered have complete information  
for the trouble
codes and repairs.
See SJM for clearing codes since these are ECU codes.  You should  
check for codes
on a regular basis--25K km or even every oil change--and clear them  
once you have
them written down.   Then, when you have problems you will know the  
codes are fresh,
or intermittent codes are continually returning.

http://www.sjmautotechnik.com/trouble_shooting/ecuf20v.html#fcser

Tom




> -----Original Message-----
> Date: Thu, 17 May 2007 12:53:49 +1200
> From: Sam Clarkson <sam at edgetoedge.co.nz>
> Subject: [s-cars] HVAC code gurus please
> To: s-car-list at audifans.com
> Message-ID: <FE709A98-EB08-4FC4-9444-FFB9E6BB5CBB at edgetoedge.co.nz>
> Content-Type: text/plain;	charset=US-ASCII;	delsp=yes;	format=flowed
>
> Hi
> 93 S4
> I've had no heat for a while, when it first went awry i'd have heat
> on all the time unless I went to full cold, even half a degree above
> would be back to full bake. Then no heat at all. I just checked the
> servo motor it's going. Vac is sucking and is holding fine when the
> motor is off. When I suck on the heater tap servo hose it opens and
> closes fine.
> So I start the car and warm it up to pull codes the heater is now
> going!? What happened I didn't change anything?
> Codes read ch1; 8.7 and 11.7
> The 8.7 said to read channel 8 so depending on the temp setting in
> the cabin the readings on ch8 varied a lot.
> The 11.7 said to read ch11 it read a steady 23.2 regardless of temp
> changes.
> Anyone able to coach me on what's going on?
> How do I clear the codes to get a fresh set of readings? Or is that a
> bad idea?
> Audifans fan as always....
>
>
> Sam Clarkson