NO power to my a/c compressor

You are totally wasting your time. Sorry to say, but this needs to go an International dealer. The A/C system is totally controlled by the International body controller. There is really nothing you can do to properly diagnose this without International software.

 

Probably not related. There are several body controller software updates that get released all the time. There was a big one just for the A/C a while back. I understand some people do not like dealers, but this is one case where you are kinda stuck going to one for this issue. If you do go, make sure they update your body controller.

 

High pressure sensor could be a likely culprit. The body controller will monitor the a/c system pressure through the high pressure sensor. Once the pressure is about 300 psi it will tell the engine to turn the fan on. If the a/c pressure continues to rise over about 350 the body controller will log an a/c high pressure fault which will lock out the a/c operation until the next key cycle. Does your fan come on at all? If not, does your truck have a fan override switch, and if so does it work? I have seen where after trucks have been boosted to start some parameters for the engine get reset and the engine will actually ignore the fan on command from the body controller and cause issues like this.

 

Well, that is totally up to you. That is the only part you can replace without needing either an a/c machine or a laptop.