The thermistor (thermostat for the AC) with the knob on the front panel area near the radio controls a relay (maybe relays) for the AC compressor and the fan in the engine bay. When turned completely counterclockwise it turns off the both the compressor and the condenser fan. That knob can be stubborn to turn off when twisting counterclockwise. Make sure you actually feel it clunk off. Try clunking it both on and off.
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