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Discussion Starter #1
Ok - here to bounce one off the other Techs. Got a '95 GT - A/C just quit. Static pressure within acceptable limits. Ran all pinpoint tests per Ford shop manual. Get to pinpoint test C9 - (Check CCRM PIN22 - Circuit 331 - PK/Y - Output to PCM) - interrupt PIN22 / circuit 331 at CCRM - and A/C clutch engages and pressures are normal. Circuit 331 is the PCM WOT cutout. This points to the PCM as the potential suspect. Everything else operates normally. Anybody else experience this? As I went through the checklist everything was pointing more and more toward a bad CCRM - which I was expecting as I moved further along, but before I got to that point (pinpoint test C10) pinpoint test C9 is telling me I have an internal fault in the PCM. I have to be honest - I was not expecting that one.

PS - KOEO = 111/10/111

Thoughts?
 

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post your diagram

forget the shop manual tests, they are relatively useless.
 

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I see the high cutout, is that closed?

then you need page 54-2, must follow backwards from "A"
 

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Discussion Starter #5
High press cutout functions as intended. Cycling pressure switch checks out (jumpered). I have power on circuit 198 (DG/O wire) within 1" of C192 at CCRM. No power out on circuit 347 (CCRM pin 23) to A/C field. Everything checks out. I cut the ground side switch (circuit 331 - PK/Y wire) and compressor immediately engages. Circuit 331 (PK/Y) is WOT cutout at the PCM. It's a ground-side switched circuit. My thoughts are that the PK/Y wire has a short to ground somewhere between CCRM and PCM as everything else is operating as designed. I have to remove the harness at the pcm and check that PK/Y wire to rule out short to ground. If resistance checks out, I think I'm looking at a PCM problem. Strange thing is, I've never seen a WOT cutout in a PCM take a dump like this, while everything else is working as designed.
 

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unplug c192 and c294

test light to batt positive and check for a ground on 331 at both connectors
 
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