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Discussion Starter #1
Ok so the car is a 95 GT of course with 187k. AC is all original. For the past two months the a/c worked. It took a few minutes to get good and cold but it worked pretty darn good. The previous owner said he had to refill it every two or three years but had not had to in a while. I plan to replace the connection fittings on the high side and low side when I can afford to pay the hobby shop on base to vacuum her down for me and then recharge.

So part two of the story I seem to remember it working still when driving it to the body shop to be painted. I had a check engine light after pulling a huge hill but that turned out to be something unrelated and was nothing serious that seemed to have anything to do with the a/c system. So After I picked up the car from the body shop the a/c was not working at all on the drive home. They put some miles on the care to drive it to th actual location it was going to be painted. I also had a new hood installed and they removed the grounding straps to the factory hood as well as the harness to the underhood light. One wire was hanging out of the underhood light harness shorting out on the chassis but I taped it all off and found zero blown fuses.

Work I have done so far: Jumped low pressure swithc and compressor kicks in. I put the switch back on and hooked up a can of freon. Compressor kicked on for a few seconds and went off. The crappy gauge showed pressure around like 55 psi but I doubt it was accurate. Ambient was around 50 degrees if that matters and engine was at almost normal temp. Fan was also running. Shook the can and nothing still. Turned everything off and started car again. Jumped the switch and compressor came on. I didn't wait to see if it got cold because I did not want to damage the compressor.

Anyway I hooked the can back up and jumped the low pressure switch with it connected and compressor cam on but was not pulling anything from the can. The can is still full after all this and it's a small can. Now when I turn the a/c on the fan is not automatically coming on the past couple times. PLEASE give me some advice what to check next. I am new to anything older than a 4.6 so you may need to give good details lol. Thanks!
 

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The most common reason for the compressor to not kick on when it is full of freon is the A/C cycling switch. Its on the receiver-dryer (a large, painted black cylinder with two hoses connected to it on the passenger side, near the fire-wall and under the passenger hood hinge). With the engine running and the A/C switch on, disconnect the switch and use a piece of wire with the ends bare and jumper across the harness side of the connection. If the compressor comes on, replace the switch. It just unscrews from the top of the dryer. There is a supposed to be a valve under it to keep refrigerant from escaping, so that should not be a worry. If it does leak, you will just have to recharge the system.

Good luck!
 

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Discussion Starter #3
Went back outside to test some more. Jumpered low pressure switch and started the car. Compressor runs as does cooling fan. A/c never got cold after 1-2 minutes. Hooked up freon cna and gauge read almost 0 psi. It never took any freon from the can either and ac stayed warm. Turned it all off before anything could get damaged. Went back and looked at gauge and it was at 55 psi on low side with engine off. Ugh what is this things deal?!
 

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Discussion Starter #4
The most common reason for the compressor to not kick on when it is full of freon is the A/C cycling switch. Its on the receiver-dryer (a large, painted black cylinder with two hoses connected to it on the passenger side, near the fire-wall and under the passenger hood hinge). With the engine running and the A/C switch on, disconnect the switch and use a piece of wire with the ends bare and jumper across the harness side of the connection. If the compressor comes on, replace the switch. It just unscrews from the top of the dryer. There is a supposed to be a valve under it to keep refrigerant from escaping, so that should not be a worry. If it does leak, you will just have to recharge the system.

Good luck!
Is that the same switch as the low pressure switch I already jumpered? If not do you have a picture of it maybe? I don't want to be jumpering the wrong thing lol
 

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If the switch is on the black canister as described, it is the same switch. There is only one switch there that I am aware of.

The "deal" I don't know about....gremlins????
 

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Discussion Starter #6
If the switch is on the black canister as described, it is the same switch. There is only one switch there that I am aware of.

The "deal" I don't know about....gremlins????
Yeah pretty sure we are talking about the same switch since when I jump it the compressor comes on lol. But can't figure out why the gauge is reading zero psi almost but it won't pull any freon from the can then goes to 55 psi when I shut off the car. Wish I could afford to just take it somewhere.
 

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Discussion Starter #7
Well I figured out why it won't take the charge....the stupid gauge I was using was from a different kit and has no freaking needle to puncture the can. So I am out of luck until I can get what I need.
 
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