A/C issues i cannot figure out what is going on, Please help 3 Weeks!

Details: 2011 Mustang base. V6 manual trans:
My daughters car no a/c. first checked with gauges system blows just warm. System was low, Pulled vacuum, no leaks. Went to charge pressure both sides super high. Restriction. (note even when charging the A/c clutch would not engage. Ran jumper system not taking charge, restriction. Replaced hi/low pressure switch, no go. Replaced condensor and expansion valve. pull vacuum, no leaks. to to charge won't pull in charge even with jumper on compressor. relay and fuses good. I am down to either the a/c control module is bad or the compressor. Compressor clutch will not engauge unless jumpered, soon as jumper off clutch quits. Ran codes, no codes. scanner can do some A/C scans put no ECM. The ending gauge readings after replacement and trying to charge was 90 on low side 100 on high side. What am i missing and what else can i check? Thanks

What were pressures when compressor was running with the jumper? And fyi with most a/c charge level issues there won't be a code from it. How much r134 have you put into the a/c system?

About the only way I can see both problems sharing a common cause is if no freon is getting into the system. So there might be something going on with your gauge set? Maybe test it on another vehicle.

Below is from an '08 Mercury. Aftermarket AC pressure sensor telling the PCM the system was under vacuum!! This didn't set a code but did stop the compressor from engaging. Should give you an idea of what PIDs to go after if you don't find anything wrong with the gauge set.

 

100 low 100 high barley 1 can

qauges are working properly tested on multiple vehicles, its in the system that won't enguage compressor

One 12 oz can or the big 20 oz ones?

not even a full 12 oz, it won't take in the freon

Is this automatic climate control? Or, Manual climate control?

When you use a "jumper" to engage the AC clutch, are you jumping both power and ground? Or, just power? Or, just ground?

If it barely took one 12 oz can and has 100 psi on hi and low side are you charging through the low side only? Did you draw a vac through low side with high side closed off?Because it seems your not evacuating/vacuuming the system down to 30 inch of hg for 30 minutes. So either the h block/ office tube is stuck/ plugged up or your steps for evacuating and recharge is incorrect or you missed something. This is a mechanical issue not a electrical one with the charge not going in like it should

wrote:

This is a mechanical issue not a electrical one with the charge not going in like it should


 

If  the  clutch does not kick in, it will be near impossible to fully charge. You need the Low side pressure to be lower than the pressure in the can of freon.  With out the clutch the engaging, the Low side and High side will equalize pressure with the can. Once the  pressure is equal, flow stops.

I agree with the fully charging part Chad but the first 12 oz can not going into system is the issue. Every a/c system I have charged always took the entire first 12 oz can without having to have the compressor cycling furthermore none of them ever reached 100 psi on both gauges with the first can. As well as with the case of this mustang the first two cans should go in without having to cycle compressor. Which is why I came to the conclusion of mine. No hard feelings here just my point of view/process.

I don't use the 12 oz cans. I charge from a 30 lb tank, so I really can't say  how many 12 oz cans should go in before the clutch kicks in. I trust what you say is true, Alex.  However, with 100 psi on the low side and the high side, I would expect the clutch to engage, regardless of a restriction, unless it has been dis-allowed by the PCM. But, I have been wrong, many times, before.


Is there any change in the pressures, at all, when the clutch is jumped? (be sure the High side valve is closed on the manifold/gauge set)

 

first the "Procedure" for a charge is correct, it is hooked up correctly. its a manual climate control. to get the compressor to kick in i can jumper from the purple wire going into compressor to a battery hot. after 1 can the compressor should kick in ,without the jumper it does not. i am thinking there is an issue with the hVAC control module

manual control. jumper from purple wire on compressor to battery

I think that the relay is not being commanded by the PCM for some reason.

If you have a scan tool, you should be able to see if the PCM is receiving a request to engage the Clutch relay. You should, also, be able to see if the request is allowed, or denied.

What happens to the pressures when you are attempting to charge, and you manually engage / jump the clutch?

 

i think compressor is shot, bet shaft is broken off inside. you get the initial rush in then thats it