Wiring and PCM Help

Jaymes Dread

New Member
Jul 7, 2018
2
0
1
Oklahoma
Im new to the mustang world but not new to the mechanical world. Long story short, I have codes for EGR circuit, EVAP Purge Circuit fault, AC clutch circuit, HO2S faults, and Ive tested all the components as well as i can without having the service manual in hand. I recently bought a used 02/2010 v6 with 106K MIles. I've followed other threads that have the online pdf and downloadable pdfs, however Ive found they are both incomplete without all the pinpoint tests, specifically HX. Ive also found other posts and replies that talk about checking fuse 47 and 8, Ive tested everything I can think of from voltage to resistance, and removing all the harness loom to visually inspect the wires to and from all the components. I have come to the educated guess that my pcm and/or harness is bad and Im going to replace both. I have found reman and even new PCMs for relatively cheap, and many different kinds of harnesses. My main issue at this point is i cannot find the proper part number for the correct harness that contains the EGR, EVAP, AC, and HO2S. Ive searched the ford parts website and found numbers but the images they have do not prove any hope that 550 bucks would be well spent on the correct one. If anyone can help with the part number that would be great. If it helps, my PCM number is AR3A-12650-UC, UUH2,
 
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Ive even removed the fuse box and PCM to clean all body to bracket grounding surfaces, Ive cleaned the grounds on the front brace, the ground in the back of the block to the firewall, removed the starter and cleaned the mating surfaces, and even added a ground from the battery-to-wheelwell directly to the PCM bolt on the bracket. I know that the ground isnt and issue, and I have full voltage and alternator activation. Ive tested the alternator diodes, rectifiers and its puting out DC. I had hoped that maybe it was feeding back AC once in a while since that would be a cheaper and easier fix but thats not it either.