An update. Donbrew, I can jump the clutch terminal and it engages to the compressor. Relay tested good, swapped it with 2 more to be sure. Doesnt look like im getting power to the relay point 87. pretty sure that means I need to trace grounds and check under waterfall to see if something is loose. I have a feeling a contact when I press the AC button isnt completing the circuit to allow it to trigger.

going to check AC relay in BCM and if it works I know the problem lies between ac controlls and bcm.

Random thought, I may have burnt my compressor up when I thought about it. My HO alt had a half inch shorter pulley. I was told to use a half inch shorter belt which was 5050400 when someone didn't realize 06s used that as stock and others used 405. I got a 395 belt to put on. Going to check compressor operation Tuesday when my gauges get here if ac doesnt work when I jump the clutch.

And holy cow I see why you guys say burp it for several days. First time, it took a little over one quart. Going to do this on an incline for a couple days and redo the flush completely as it looked like green coolant was used.

 

Why would you think a half inch shorter belt would "burn up" the compressor ? Not like it's going to increase the AC pulley speed very much.
And pulling the other stuff apart to check. 1st, have you checked (or jumped) that pressure switch yet ?
Used to work on auto AC's long time ago. Pressure switch was something I would always check first.

 

Nothing is happening when I jump the pressure switch. Its not getting voltage it looks like. And the half inch shorter belt prevents the belt from slipping. Half inch doesnt seem a lot but the ac compressor puts ALOT of strain on the motor from what ive seen.

And I didnt look further into the pressure switch yet due to if I can get the clutch to engage and AC to work I will be able to eliminate a lot and know a better area to check.

 

The belt tensioner; if the belt goes around it the tension stays the same. Look at the diagram again, I think you were jumping the wrong terminals. Of course, do it while the AC button is lit. (gray and org/blk; 5volt to signal),

If there is no power on 87 the relay is open. 30 and 85 should be hot. 30 is fed by the pwrtrn relay/fuse, 85 always hot.

 

Edit of my earlier post:
Using a shorter belt will not change the compressor pulley speed. I was thinking about a shorter or smaller pulley itself.

 

On the clutch relay, 85 and 86 were hot. 30 had bo power to it. When I checked operation the pwrtrn relay, it was functional.

I double checked ac switch and had power at the low reference only. I tried jumping 2 to 3 and realized my jumper cable may NOT have been making contact do to being to big. Looking for a paper click as we speak. Do I want car running, ac turned on for this test or am I leaving it off with ac button on to listen for a click?

i went back, car started, AC full blast and jumped the compressor. I went to tns cabin and noticed no difference on temperature so thought about okay I need the fan to be on as Its off when its supposed to be coming on when AC is on. I jump fan and same thing, no change im temperature.

Wouldnt ac be forced to work if fan and compressor was functioning? Its looking like I could have a burnt compressor or got a leak out of nowhere. Going to have to wait until tuesday to test the system to see whats going on.

 

I am getting no power to my fan when I have the AC running. I checked power at my low pressure switch and the only one that has power going to it is the low reference signal. That ground is controlled by the ECM if I am not mistaken. So basically the computer is telling it conditions arent met to turn the Ac on?

If I jump 12v to the switch signal(pin3) and it works, would that bypass the low ref signal?

Looking at these diagrams, only thing I can see is I believe something before the Ecm is not telling the ecm to switch the ac on.

Can the temperature actuator cause it to not come on?

 

So I ended up checking low side, it I guess had 0 Freon on it, no idea why out of nowhere, added freon to it with a gauge and went to roughly 35 psi and didnt turn compressor on. Shook it to take it to 40 with same result. When I took the can off the low side, I heard the shrader valve leaking which was leaking due to extremely cold weather and age or possibly stuck open from the can?

Clutch didnt engage and fan stayed off. I am honestly at a loss. I dont know what else to try. Unless the ecm is commanding the air not work, but with it having low side full, I jumped clutch, it engaged but no air came out. Usually when you engage the clutch on a working system the car bogs a little from it coming on but doesnt do that. Could that mean the piston inside the compressor or something broke and it cant create the pressure needed?

 

What does "no air came out" mean?

Possibilities:
pressure too high
pressure too low
broken pressure sensor
broken compressor
broken clutch
broken switch
broken circ fan (AC won't run without it turned on); I have been assUmeing you know that.
broken relay
broken diode
broken fuse
broken/poor contact wires

 

30-40 psi... it's still low on freon.
Full static pressure on the AC system will be about 100-110. You need more freon.