CAT 966L Aircon not working

CAT 966L loader's air conditioning is not working. The Fan are working. I checked aircon fuse F17 on the fuse box the power is there but if you switch on the Aircon pump switch there is no power going to the Aircon pump clutch. When i tried to check the Aircon switch i saw many wires plugged in to the switch then i became stupid since i didn't have an electrical circuit of the Aircon
Am asking for help . Thank you in advance

The serial number is
CAT0966LPFRS01538