Did you start the car while you were putting on Freon?

Cut your losses, go ahead and have an AC shop do the re-charge. They can vacuum it down like it's supposed to be, check for leaks, and supply the correct refrigerant and oil mixture.

Why send it to a shop when they sell these conversion kits? The system was empty before I put it in, and the supplied freon/oil mixture should be correct in each bottle. The only part that should require a shop is evacuating the R12.

I do have the car running when attempting to recharge the system. The procedure is to turn the A/C on full and then connect the bottle to the low side port. Located on the compressor itself in this case. Apparently the pressure in the system is higher than the pressure in the bottle and it will not take a charge. The trouble shooting guide says that either the system is fully charged/overcharged or the compressor itself is not running. If the compressor is not running, then the freon is not getting past the compressor and filling the system. I can try to disconnect the wires leading to the compressor and see if it is not engaging, or if it is engaging, then it is not functioning correctly and I need to source a working unit.

We did some trouble shooting last night and discovered that the compressor is in fact not engaging. I can apply 12v directly to the power wire for the compressor and it will kick on. The relays seem fine, but there is an issue somewhere near there. I have resistance from the relay to the compressor connection. The A/C switch does turn on the fans, so there doesn't seem to be an issue there. Where else can I look? There doesn't seem to be a wiring diagram for the A/C system that I can find. Are there any sources for this part of the wiring harness? What else can I try?

The compressor won't engage if there's nothing in the system for it to compress. You have to jump it to get it charged.

Ok. I'll try that. I'm just going to apply 12v to the compressor. Correct? I assume the compressor takes 12v and there's no resistor to reduce voltage.

Have you evacuated the system, it is my understanding that for the system to take the charge you need to create a vacuum in the system itself. Harbor freights sells air compressor powered vacuum pumps for creating the vacuum and they are only like 10 dollars. If you just put all the ac back in then I am guessing you also have air in the lines that you have to get out before charging, which the vacuum pump will also do as well.

I'm still not sure where the problem is. I jumped the compressor power wire and I did manage to charge the system. However, the compressor will not come on with the A/C switch. The relay seems fine. The other relay (for the fan) works fine. All fuses are good and I do have resistance between the compressor power wire and the relay. I'm guessing the relay itself is not coming on for some reason.

When we test for current in the relay while the A/C is on, there is power to all wires except the compressor power wire. I've switched out relays and still nothing. Something was mentioned about the pressure switch that can keep the compressor from kicking on. Can I test that switch to see if it's bad? I have good access to it since it's mounted to the firewall. (different on my Colt than a DSM) Where else could there be an issue? I might break down and take it to a shop, but I doubt they will have any more success than me. Unless of course they are familiar with this particular type of system.

Your AC control unit is dead. There are no more.

Are you adding to the low pressure side?

If you done have enough freon in your system the compressor want engage also. It has a pressure switch somewere that reads howmuch pressure is in the system. I would find the switch and test it and i believe you can use a jumper wire on it to connect both sides of the wire and see if your compressor will engage that way. But besure to test the wire first as im not 100% sure on jumping the wires on the colt. I know on american cars and hondas that is what i have done in the past.

The pressure switch is on the drier, next to the sight glass. Driver's side of the radiator.

But I fear that's not the issue.

Well, my step-dad happened to have a vacuum setup for A/C systems and we vacuumed the system out. A must. And recharged the system. I have about 20oz of refrigerant in the system, but the compressor still refuses to come on unless i jump it. I haven't tried to bypass the pressure switch yet, but I will try that. I know there is pressure in the system, although it may be low. We're not 100% sure the compressor is all that good. It does blow cool air, so it should work for now. Some good news is there aren't any leaks in the system. Yet.

Worse case scenario, I wire in a separate switch to turn the compressor on. Isn't there a switch that turns the compressor off when your at 80% throttle or something? Maybe there's an issue there.

There's an AC control unit which is the brains of the system. They burn out. They're not made anymore.

Do the Colts have a temperature switch on the thermostat housing like the DSM's? I had a similar issue with my '91 Talon. The inside of the switch came apart. Just a thought.

I'll check about the thermo switch. The Colt is basically a 90 DSM with a Mirage firewall and chassis harness. The A/C harness I got came from a 91 Mirage 4 door and was a plug in deal with this Colt, as well as the A/C lines, condenser, and drier. The A/C compressor was a unit from a 91 Galant SOHC 2.0L, as well as one of the A/C lines.

I'll have to check out the A/C control unit. Where is it located and how do I test it? I assume I can pick another one up at the junk yard, but I'll need to test that one as well to make sure it works. If I can't get the control unit to work, can I just put a jumper wire on the compressor and turn it on with a separate switch?

alright I just recharged my a/c a couple days ago and I couldn't get it to take a charge either. I was getting really frustrated with the instructions supplied with the kit. When I opened the bottle it pegged the needle on the gauge on the high pressure side. So I pulled it off and jettisoned the contents of the bottle. I couldn't figure it out but decided to check the fuses just in case and one of them was blown. Plugged a new one in and it sucked out the remaining bottles real quick, now I have nice chilly a/c. Just thought it may be something simple you overlooked.

It's definitely not a fuse or relay, but thanks for the advice. Sometimes we do overlook those little things. Right now, I think Defiant is right. Somewhere the A/C control unit is not correctly communicating to the compressor. I have another friend that is having the same issue as me.

I was told not to attach a separate switch to the compressor, as it will eventually burn up the compressor. The compressor was not intended to run constantly and that's what the control unit was for. I'll have to find out where that thing is and if I can change it out. I have the factory wiring diagrams, but I'll have to see if I can even find the control unit. Then it's hit and miss to find a car with a working unit.