Does anyone have a proper circuit schematic for a Ford BA series PCM?

2003 FORD FAIRMONT
80,000 MILES • 4.0L • 6 CYL
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VALLEYKING
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This model has a common problem with old PCMs developing cracks on the circuit board, meaning they won't start when cold. Replacement parts are no longer manufactured nor is there a compatible generic solution. In order to find the location of the error to effect repairs, I am looking for a circuit schematic of the PCM (note not a pinout/wiring diagram which are readily available and of no help).
Jun 14, 2025 at 10:22 PM
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STRAILER
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Yep, bummer, sorry only the manufacturers would have that diagram that I know of. Can you get a used unit? They are plug and play.
Jun 15, 2025 at 11:25 AM
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VALLEYKING
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They aren't plug and play. They are coded to match the vehicle computer and console. Any mismatch between the 3 and that part of the car won't work, so it needs to be specially recoded turning a $60 repair into a $1,000+ repair because of the specialist equipment required.
Jun 15, 2025 at 9:11 PM
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STRAILER
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And there you go; I have swapped out the engine computer before and they worked for the crown vic's but maybe it is different for the Fairmount.
Jun 16, 2025 at 10:11 AM