And the pressure in the system needs to be satisfied (enough pressure) or the clutch will not pull in. This is to prevent running the compressor 'dry' which will destroy it.
Yes, the fan should run as soon as you call for A/C regardless of anthing else. Possibly low speed initially, then kicking to high for sure when the recirculate button is in.
I suggest rolling the windows down until you have the cake to bring it to a competent shop. It needs to be thoroughly checked, and the lack of A/C switch may be for a reason other than the radio being stolen (and who would steal these radios? They are garbage!
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