2000 Ford Mustang Air Compressor will not engage

Ok so tell me did you replace just the compressor or was it with the clutch? If it was with the clutch was the clutch already on the compressor or did you have to put it on? Let me know and we will go from there.

I purchased a remanufactured air compressor with the clutch already installed. I took the car to a A/C shop to have it charged (no leaks, system charged) and they could not get power to compressor.

Just before the air compressor stopped working (took the car in for leak test and they found the front seal on the compressor was leaking, lost all of the R134) the A/C stopped working for a day and then started working again for approx a week. Strange?

Quick question, does the car have a clutch switch and A/C high pressure cutout fan switch? If so, where is the other switch? I already checked out the switch that is attached to the accum/drier.

The A/C shop just called and said they removed the freon and re-charged the system (2 lbs Freon) and never got the compressor to engage during the recharge. The shop does not get the same pressures as the mechanic I hired last night that hooked up AC gauges (low pressure reading 390psi).
Last night, the mechanic wired the compressor to the battery for only 5-10 seconds and was able to engage the compressor/clutch and cold air started blowing.

Results

1) The compressor and clutch work when hooked to the battery but will not engage when connected through the wiring harness/system (no power in the wire hooked to the compressor).
2) Both mechanics do not get the same pressure readings.
3) Jumpered the pressure switch on the accum/drier and can not get compressor/clutch to engage
4) Used a test light on the pressure switch harness and have good voltage
5) Both A/C fuses under the hood and under the dash are good.
6) I have replaced the air compressor/clutch, accum/drier and lower liquid A/C line. No leaks.


At this point in time, I am thinking the CCRM is the problem. Everyone tells me that the CCRM is the last component to fail and is not always the problem. Very frustrated!



Thank you,
Randy

Looks like you need to test the pink/yellow wire at the CCRM to see if the PCM is signaling the comp to turn on.If it has signal, the CCRM is probably bad, they do fail often and from what you describe may be part of why the system worked intermittently before the parts were replaced

Thank you! Can it be tested with a test light or volt meter? Do i test it while it is connected? I will need to remove the inside fender to access the CCRM.

use a volt meter with all plugged in.Just find th wiring harness that goes to it and then the wire I told you. that way you dont hv to get total access to it

Last question, do I need to have the car running with the A/C turned to MAX in order to test the harness going into the CCRM. What kind of a reading show I be looking for on the volt meter?

As long as the air is on it should be ok, Max is just recirculating the inside air.Hard to tell from my wiring diagram, it will either be 12 volts or ground trigger for the relay

thanks Jack for covering. Verizon was down all morning so I couldn't answer it would let me log in and look at the question then expire the page. I checked with verizon and they said yea they were aware and that I probable couldn't get into other sites too. If I can be of any help from here just let me know.

The CCRM seems to be the problem! I wanted to thank you for all of your help!! You nailed the problem!!

Great work, that is what we are here for. Thanks for you support. Thanks Jack for stepping in here when I was having internet problems.