I have 2003 S 60 2.4t The a/c starts out good when I first start the car. Then as it gets to cold in the car I turn it down that is when I have a problem with it. It gets to a point where it is hardly blowing out air no matter high high or low the fan control is. If I turn it off for a few minutes then it will start working again I don't know if it is related but one of the lines is frozen in the engine compartment. Already Tried: Changing the cabin air filter
You have a bad evaporator temp switch, It is not shutting the compressor of when the temp gets too low, and your evaporator is freezing over, thus the insufficient air flow, when the evap melts, its blows again. You need to replace this switch. You just remove the harness, then remove the switch and install the new one. See above diagram.