I have a 2009 screw Fx4. The a/c compressor will not stop cycling. The a/c had, and still has a hard time keeping up on a hot day. The dealer said I needed a new compressor. When the dealer recharged the system, he said he found a leak in the condenser, and it had to be replaced. When I went to pick it up, (with new compressor, condenser, and dryer, $$$), I ran it through it's cycles. The compressor still will not turn off, even if I deselect the a/c button the control panel. No matter matter which selection or temperature I choose, (vent, defrost, heater, a/c) the compressor still cycles. The only way to stop the compressor from cycling is to turn the power off to the entire climate conto panel. This is the exact original reason I took it to the dealer. The a/c still has a hard time keeping up on a hot day. The dealer kept it for a few days, and then called me to come pick it up. He told me to take it home and that he was consulting with Ford engineers, and that he would call me when they got back with him. Oh, the relay and fuses have been replaced. I hope someone here can help. Thanks in advance for help.

 

My 2011 5.0 does the exact same thing. Just fans on, no AC. 'oops, I notice you don't have the AC on... here let me turn it on for you!' Only way off is to power down climate control. This only seems to happen to me in summer though.