I have a 2001 Pontiac Grand Prix, 3800 Series Non Supercharged. Im having a problem with my air conditioner. On my dash panel I have a AC button that when I push it should make a light come on. But, my light will stay on all the time when either pushed once or twice. And It only comes on If I turn the fan control on. So, I first try the air after running the car for atleast ten minutes and it has no cold air coming out. Then I push the AC button again and the same thing happens with no cold air coming out. I thought about speding the $30.00 to get the refill can of freon at walmart but I dont want to get it till I know if there might be something else going wrong sence that AC button will always stay lit when the fan motor is turned on..
Any ideas on how to trouble shoot or if anyone else had this problem could give me some thing to look for or try..I usually dont ever use my air sence it uses more gas it seems but with this 100 degree temps we have been having it makes me want to use it...

sounds more like a controller problem, if it was low you wouldnt be getting weird indications

I will try and add a can of freon and see if the AC light goes on and off. Is the line I hook it to in the back of the engine? I have one line in the back and one on the right side in the middle..

quick disconnect will only fit the right one

I went to walmart yesterday and bought a can of Interdynamics EZ Chill R-134a Refrigerant plus oil with system-safe Leak Sealer. I read the instructions on the can and I started the car and turned on the fan to max and on the coldest setting on the AC, I then waited two minutes to see if the AC clutch thing to ingadge and it didnt start spinning. So as it says on the can I hooked up the tube to the correct port with the black cap toward the back on the firewall and started adding freon from can. After a minute of adding the freon, then the AC clutch thing started spinning. I shook the can like the directions said while adding the freon and after about 3 minutes each time I would release the button on the can, then the gauge kept showing 25 psi. I then kept the button pushed on the can to keep adding more of the freon but it wouldnt go past the 25 psi mark on the gauge. It also started bubbling some liquid out of the area where I screwed the gauge hose to the can of freon. So I took it off from the port and put the cap back on and got in the car and the air was a little cooler then before. I then turned off the car after 5 minutes and went inside to get ready for work and after 45 minutes I then went to work and when turned on the air it didnt seem as cold.. Would the can I bought maybe be defective or should I try connecting the can again and let it sit longer connected to the port. Maybe I didnt leave it on long enough..
Also, the AC light that I mentioned in my above post I figured out that it will only stay on when I have the fan on the max setting. So I figured out that problem...

if the thing was that low you are going to need a couple cans maybe 3 if they were the small ones and they get slower as they start to equalize pressure. (the can gets empty and the car gets full)

Thats a good point. I tryed the air today but it came out hot. I will try to add the rest of this bottle. Is there a way to tell if its leaking before spending more money on another can. The gauge that came with the can shows the green area is between 0 and 25 psi, and the blue area is 25 to 45 psi which says it needs filled in that area, and the yellow area is between 45 and 65 psi which says Alert. When I first hooked it up, the gauge read 25 psi and as I was filling it the gauge only went up to 28 psi and thats where it stayed. I supose I could go out and hook the gauge on and see if its still reading 28 psi to se if it maybe leaking if its down...Im thinking sence its been over 100 degrees the past 3 days and between 95 and 100 degrees the 2 weeks before 3 days ago that maybe the heat is making the AC runner harder..

If the compressor came on WHILE filling it with the can, then yes, you were low on freon. How much freon you lost is unknown. How much you will lose, who knows? Find the stuff that has the flourescent dye in it and put that in.

Where do i get some with the dye in it?

Autozone, Advance. Just look for the A/C stuff.