I am not sure what model you have or how they wired it internally, but I do know that a lot of electrical systems will have power applied to a component, (such as your freeze sensor) and will switch the ground onto and off of the component. When you check the component, because the ground is not connected, it will show the voltage (14.5 VDC??) on both wires. But, as I said, I don't know if the freeze sensor is a switch that closes or one that Opens when activated.
If your AC is a name brand such as Dometic, you can contact their customer service and ask their technicians for help.
Also, please try to clarify if the voltage is there on the AC and the fan, but the AC is not working.