Okay I have 2000 jetta 1.8T. AC just stopped working, Had an issue with the FCM(fan control module) replaced it. Yet still no AC. Pressure switch has been tested fine (DUTY CYCLE @ 20%), Engine ECM tells me with vag-com AC passed, and under the readings I can see all the switching is operational. Freon level has been checked and no leaks present. One odd thing I noticed is that the voltage to the ac compressor seems to be switching from 12V to
0V (pulses) fairly quickly, quick enough that it doesnt allow the ac clutch to activate. What would cause such a problem or prevent the AC clutch signal from acting the way it should. Bently manual doesnt provide enough insight into the workings of the FCM (Fan control module) and the type of signals it receives or sends. Wiring diagram only goes so far. Damn volkswagen and their secrecy.
Thanks Alex snipped-for-privacy@internet.look.ca