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The A/C system can be complex, as there is an ambient temp sensor that will not allow it to turn on until it is 56 degrees- and a high and low pressure switch that will also not allow it to run if the freon charge is less than about 50% of the full charge spec. Pressure in the system won't tell you the quantity of freon- so you need to be able to evacuate the system fully, and charge it with a measured weight of freon, according to the sticker on the radiator support. You can't use the compressor to pull freon into the system, as it won't turn on if low
Like I said, there is more complexity to it than just that. It could be any number of issues, and it also depends on whether you have manual (dial) controls or the Climatronic system with digital display. Typically anytime A/C work is diagnosed, the first thing to do is to evacuate the system, leak test it, and then charge it with the proper level of freon- which needs to be set precisely BY WEIGHT with an A/C machine. using any kind of refill "kit" is just guessing, and there is no way to know if your system is already up to full charge right now and has an electrical sensor issue.