First of all, I would like to mention that I am a woman and do not know much about cars but am looking to seek help with my a/c problem.
I have a 2004 Pacifica, the a/c control module was not working and only blew air from the defrost. I went to a place where they repair a/c's and they said the control module was faulty and needed to be replaced. Since he did not have the part, he manually opened the vents from the front so we could get cool air when we turned it on. It was not enough for very hot days but when it was warm, it did feel cold.
Then we found a control module in a junk yard, we replaced it and everything seemed to work fine, but now it was not throwing cold air. We took it to a place where they repair a/c's and they supposedly checked everything, compressor working, and all the components were working. But what he did notice now was that the compressor would turn on for about 10 seconds, throwing cold air, then it would turn off and throw regular temperature air. Then again cold air and so forth. He said nothing is wrong with the a/c or the wiring, and that most likely there is a mechanical problem, and the a/c in a way is trying to defend itself by turning off the compressor. Does this make sense? I just had a big repair in my Pacifica a month ago and all mechanical issues should have been fixed. The computer is on only because of the catalyst needs replacement but from what we know that is it. We have a faulty radiator cap which causes the water to boil, but I don't think this would be an issue. The car doesn't get hot, or at least it doesn't say in the display. Anybody have a clue why the compressor would turn on and off repeatedly?

 

Low freon or radiator fans not turning on

 

Well according to them, it did have enough Freon. The fans are turning on as well.