So to start I have a 2008 s60 2.5 T. I've spent countless hours and $$$ trying to diagnos what in the world is going on. I've rechsrged the A/C system. I've released some charge. I've chsrged it again. The clutch would sparatically engage for a few seconds here and there. I got the idea to check the relay. Tested fine. With the cover off and manually triggering the relay the clutch engages. So I pulled the relay and jumped the connection to keep it running so I could get an accurate recharge and reading on my gauge set. At 85°F my low side is between 30-45 and my hi side is between 150-200. To my knowledge this should be correct. However something just will not keep the clutch engaged and I can't keep a jumper cable in place for obvious reasons. Is there some sort of sensor that can be replace so that I don't have to take it do a mechanic or Volvo dealer. I'm trying to avoid replacing the compressor but that really doesn't seem like the issue from what I've discovered. I just don't want to have to sell a kidney to get this repaired. Please any I sight will be greatly appreciated!

 

And I also typed this up on an iPhone. Just to clarify that I'm really not illitarate hah

 

Older volvos (850s and Gen 1 s40s) are known to be prone to clutch gap issues where as the AC clutch wears it can't create enough pressure and the slippage builds heat and trips the compressor off. Symptoms are typically the AC runs when cold for a few minutes then shuts off until it cools down. See if you can measure the gap with a feeler gauge (should be in the 3-5 mm range). Other than that, you may have a faulty pressure sensor - you may be able to remove the connector to the sensors one by one and jumper with a paper clip to see if that will get the AC to kick on. Not sure about your model / year but there may actually be 3 sensors on the high side (each a different color ) down by the condensor and the low pressure sensor should be on the return tube by the firewall. (only a guess so take a look around)

 

It would appear that after leaving the batter disconnected for about an hour seems to have resolved the issue. I suppose the ECU needed a kick in the ***