Air Cond, Compresser

[ringo7]

Air Compresser Clutch not Engaging---- R-134a Refrigerant level Good; :96 Ford Windstar
I suspect the C.C.R.M. /the fans are also engaging while eng. is cool; this book is showing Relays
to Air Cond Clutch and Fans are in his unit; 98 dollars new;

[angus10]

Coolant level ? Has nothing to do with the AC.

[tripletdaddy]

Depending on the configuration they put in your van, there can be up to three sensors attached to the refrigerant lines. One on the low pressure side is the cycling switch, which will turn the compressor on and off at the normal operating pressures. The other that would affect compressor power is the high pressure cutoff switch, which will turn off the ac if its pressure gets too high. Then there is a cutoff relay used to turn off the ac for times that max acceleration power is needed, which is controlled through the CCRM, so you probably have this seperately. However, there may be a "refrigerant containment switch," a fancy name for a dual function pressure cutoff switch which will measure the pressure for the PCM to select the cooling fan speeds and will disconnect power to the compressor at too high pressure.
I would not be sure which component is defective, but the CCRM is expensive, so I'd try to rule the others out first as they are cheaper to replace and easier to test. But you would have to be comfortable and capable of testing the wiring and the parts. If done carefully and briefly, you can jump the sensors one at a time to see if it is bad.

[ringo7]

I checked for Power at Comp Clutch -Good
I ran a Hot wire from + batt post to Comp Clutch --No Click;

This is wife"s car ,there was a check eng light -
Intake manifold control fault-bank-1
Troubleshooting code #P1537
1 E.C.M. detected the signal from IMRC was less than expected-valve stuck open;
proable cause;
1-- Mechanical condition
2 - Open or shorted circuit condition

The other code #1538
Intake manifold runner control fault-Bank 2
ECM detected the signal from the I.M.R.C. was less than expected-Valve stuck open;
#1 mechanical condition
#2-Open or shorted circuit condition;
I noticed the Eng. R.P.M. would increase from750 to 800 when ever Air-Conditioner was on.It would do this every 5 seconds,
Looks like I will have to remove upper Manifold ,to access Valve; Question would this affect Comp/ Clutch; or
two seperate problems;

[ringo7]

Removed Air Intake Manifold--excessive Oil-Removed P.C.V. valve; Removed I.M.R.C,, will replace,haven't checked the cost at this time;

[tripletdaddy]

Can you measure across the two pins of the ac comp clutch? Off hand, if you are able to get power to it either by bat or wiring harness and you have confirmed ground, then the clutch field coil is no good. You will have an open circuit, short circuit to ground or very high resistance. You should be able to get that thing to energize one way or another if it is still good. The clutch alone can be replaced, but may have to be done with the ac comp pulled or at least dismounted by still pressurized. Considering the age, condition, and price, you may want to go with a complete new unit.

[derffred]

to test the the I.M.R.C. run the engine , take the vacumm hose off one I.M.R.C. and put your finger on the end of the hose, this should cause the other butterfly to move. and then replace the hose and do the same to the other butterfly.

sometimes the white plastic bushing holding the acuator in the I.M.R.C. breaks and it slips out of the hole.

I also had the 500-800 rpm, clutch cycling every few seconds (and the clogged egr ports in the upper intake) in my 98 and I had one of those bushings fall out, but I also had vacumme leaks and the problem did not go away until I fixed all of my vacumm leaks.

you may want to read my thread to see what I went through
http://www.automotiveforums.com/vbul...d.php?t=903467

as far as your AC take off the electrical connector going into the evaporator and put a wire to the 2 ends of the connector with the engine running your clutch should engage and you should get cold air, if not then you may be low on freon or have a problem in the CCRM

I also had a 95 before and one of the relays was not working and had to solder a jumper wire for it to work, you could try getting a CCRM from a wrecker, in my 95 it was located in the front by the rad and it was very rusty and I am thinking some moister got inside it

hope this helps
fred

[fdunford]

My ac cycle switch was bad. Changed it in 5 miutes (~$25) and never looked back. You may want to consider it.