transmaster

As you know my A/C system does not work. It is an electrical fault, The vacuum powered parts of the system seem to be working properly. It has the proper load of 134a. I wonder if a bad PCM could be part, or all of the problem. Every system the PCM has something to do with are working properly except for the A/C. When a PCM goes bad does everything it controls go wacky or can just one thing go out?

One part of the electrical system I have been unable to find to test is the A/C Clutch resistor/diode; see the illustration below can any of you tell me were this part is.

NGM

If I am not mistaken the diode is on the clutch. Have you checked the fuses? Is there power at the pressure switch(s)? Do you have a signal from the head unit? 1995 did not have much pcm control of the ac itself from what I gather. It goes through the PCM for WOT shutoff and for idle up when the ac is on.

transmaster

I have checked the number 6 15 amp fuse inside and it is ok, there is a 30 amp fuse in the Distribution Box in the engine compartment and it is ok as well. There is no power at the plug for the clutch. I have not done much more until I know my way around the wiring harness which thanks the Alldata I am learning. Good news about the PCM I didn't think it had much to do with the system. By the way in a 1995 F150 is it called Power Control Module, or Powertrain Control Module it is listed both ways.

I don't seem to have any power across the 15 amp fuse but I am not sure my probes are small enough to reach into the plug to measure it. I have a new and better set of probes ordered. What I wish I had was an electrical flow chart so I could get a better understanding how it moves so I can get idea of where to start to check the power flow in the system.

Good old Bill

OK, Putts, you've been around here long enough, make, model, engine, DOB, you know all that stuff. Just kidding! I like NGM and the input about the PCM, am not sure about the (power load 134a). What are you saying? The #6 fuse, understand the test lead concern. Have you tried something like a paper clip to probe with? Another thought, that #6 fuse has to be powered up in ACCY or RUN, look at the backside of the fuse panel, maybe someone spliced into or has robbed that wire for something else. Just a thought. OK, went back and re-read the original thread. You're talking Freon charge, guess who is the PUTTS now.