I need to figure out my ac compressor is not turning on . I am going to replace the low side pressure switch but I was trying to find the high side pressure switch and I can't. I have chased the highside lines and Still have not found it. Here is the specs so you have a idea what I have going on. It's a 2003 f150 with the lightning swapped engine. I installed the killerchiller and it's holding pressure so that was ok I had low side 60 psi but the high side never went above 55psi. . I ran scan a forscan lite on my phone and it's not signaling to turn the compressor on for some reason . I am thinking that one of these pressure sensors is bad. Also I need to add that a lightning performance big efan kit was installed. As far as I can tell it's installed correct only thing that I see wasn't installed was the temp sensor and I believe it's because it's on a switch to turn on and off so it's always on when driving. Iam going to try and get the plug out on the block and install the temp sensor . It's a single wire that runs to the sensor. The other 2 wires go to a on powering fuse box and the other wire is piggy backed off the ac relay.