Can anyone hel?, the aircon on my 2005 (later shape) 1.8 diesel Focus stopped working one day, just to explain I have worked on refrigeration for a number of years, I checked the gas (R134A) and found it was full, I checked the fuse and the operation of the relay again all ok. I suspected the compressor clutch was faulty as it didn't click in like it used to after a few seconds and I found one on ebay at a reasonable cost , so bought it and fitted it..... and you guessed it, still no aircon! I am looking for a diagram to check the pressure switch (4 pins) as this seems to be the next most likely thing, can anyone point me in the right direction for this info' or tell me which contacts should be made or open when the system is charged..... Thanks in advance... Dave

PS the p/switch looks like this http://www.ebay.co.uk/itm/250906948569

I would put a 12 volt feed to the compressor clutch and see if the compressor starts, if it does then the fault could well be the pressure switch. You say you have checked the relay and fuses, then it could be a break in wire that controls the compressor clutch.

Thanks for your reply, clutch is ok ....... have since blown the engine ECU by disconnecting the battery while checking the wiring loom for possible damage....... ho hum !!!!!!