HELP WITH PCM CONNECTION
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HELP WITH PCM CONNECTION
Hey sorry to start a new thread. Its been a long time without a response on my old thread. I still can't find any wire diagrams for the pcm to diagnostic link connector. I've tried a solus pro, vag can obd2 scanner , and now ae. No communication with pcm. I have power. The scanner powers on. I've searched and searched for a wire diagram or troubleshoot info for weeks now and still have found nothing. Dealership said my truck is obd2. Not sure where else to go here. I'm getting 5-7 lbs of boost max instantly under 1/2 throttle (which I thought was a little quick for these trucks). Fuel pressure is 80 psi idle with the regulator shim. A couple pinhole leaks in the welds on the downpipe. Truck seems like its missing a cylinder before it fully warms up than its fine. Hunting back and forth at shift points in between gears. Seems like it would be a lot easier to diag if I could communicate with the pcm. 96 F250 7.3 auto trans. Any help would be greatly appreciated. Oh and no check engine light on but comes on for a split second when I turn the key forward. 
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From: Livoina,La
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Ok i believe i traced the wire to the pcm. should be on the top row right next to the hold down bolt to pcm. purple wire. connected to pcm it can pull 12v useing the purple wire as ground. if i disconnect the harness from pcm i get 6 volts using same 12v source and grounding the purple wire. anyone have a pcm connector diagram to confirm this is the same purple wire before i go cuting and splicing? My question is where does the purple pin 13 (module programming signal) wire from the diagnostic connector go? Strait to the pcm?
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From: Livoina,La
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Spliced in a new wire. Pin 13 gets no connection when the pcm is disconnected but is grounded now with the pcm connected. If the first diagram is correct it looks like something is wrong with the pcm. Still no communication. I don't think its causing any drivability issues so I'll leave it until I can afford a new pcm. Thanks fordpride. I really appreciate the help. Any other input on the subject is welcome.
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Also pin 13 does not ohm out to ground like its not connected to ground(like it should). But if I connect pin 13 to the negative probe on my multimeter and 12v+batt to the positive red probe thats when I see 12 volts on the meter. I believe that means pin 13 has ground and thats where my problem is. If i'm missing something or doing something wrong please let me know.
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My ae is not working on any car. Im using a parallel port to obd2 connector on my pc and not the usb connector im suppose to use. But the solus pro will not communicate but gets power and my vag can obd2 scanner connects but reads no data, check engine light on with no codes and gets an error when I try to clear codes. I also tried a scan gauge 2 which also wouldn't communicate.
Tuned
Joined: Apr 2009
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From: OR
You're going to need a usb port or serial AE proline device. From the name, the proline device sounds like a serial adapter of some sort, IDK. The only way I can run diags and read codes with my AE, I changed the communications configuration to NON OBD2 only and the interface type to J1850 PWM.
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