Definitely run the test that Bob mentions to insure the engine fan/relay works. Otherwise, there are 2 inputs to the PCM which are the dash AC control and the clutch cycling switch (evaporator probe on most cars). These last 2 are rare failures.
I also had a car that would not kick the AC on and I traced that to dirty/corroded pins on PCM connector. Just unseating the connector and re-seating it a few times plus spraying some contact cleaner on the contacts is all it took.
I also had a car that would not kick the AC on and I traced that to dirty/corroded pins on PCM connector. Just unseating the connector and re-seating it a few times plus spraying some contact cleaner on the contacts is all it took.
