AC Only blows cold air when traveling at high speed

AC blows hot air while idling and at speeds below 40ish mph. At higher speeds, highway driving, the AC blows cold air. While running a pressure diagnostic on the low pressure port, I noticed the compressor cycles on and off… when off, the pressure registers in the green, when on, it registers in the red/high.

No issues with engine temp, etc.

Looking to get some idea of what may be causing the issue before taking it in to the mechanic.

The the electric fan when the AC is turned on. I suspect it is not running and it should be.

The condenser fan (behind the radiator) may not be operating properly. A qualified mechanic can quickly diagnose and repair this.

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My guess (if the inside fan is running) - low freon.

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