AC clutch not engaging

Check the A/c cycling switch. On Ford it is normally on the reciever drier. Unplug the switch. Use a jumper wire or thin paper clip and loop the pins on the connector. If compressor engages then replace the switch. To replace the switch you do not need to drain the refrigerant. See image below for location.

Heres a couple articles on testing wiring, they will help

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Attached below you will find the wiring diagram for the A/C circuit