[s-cars] A/C problems

[james McCarthy]

Agree - with the previous responses. I've had this issue with both of my s6's but with very different causes. If cooling is fine when running - sounds like you are getting the high pressure cut out: as Fred said make sure the high speed fan is comming on.  For my avant the wiring for the high speed fan had shorted out at the connection behind the left front headlight - due to a leaky headlight washer hose.  teh symptoms were quite dramatic - meaning ac only worked when moving.  For the sedan it was more subtle - if it had been heat soaked (parked outside for hours) it would cycle on and off until I'd been driving for a few minutes.  It would also shut off in very slow stop and go conditions on hot day.  This began to occur with increasing frequency... and finally quite completely.  Replacing the compressor solved it.  It could have been the clutch or compressor switch - but with a 13 y/o compressor - I decided just to have it done once as unfortunately
 you need to depressurise the system to swap either the switch.
jamie