Electrical problems, PCM not connecting to scan?

1995 PONTIAC TRANS AM
100,113 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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ROBOCOP50
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  • 1 POST
I bought this car 1.5 years ago and it had a few problems but hopefully I have them all fixed but my PCM will not connect to my laptop nor a scan too. It has an OBD II service port with an OBD I PCM. I am aware that a blown fuse or relay and cause this issue. Any help is greatly appreciated.
Oct 31, 2022 at 6:12 PM
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JACOBANDNICKOLAS
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Hi,

If you aren't getting power to pin 16 on the DLC, there is a fuse to check. It is the cigarette and horn fuse. So, if the horn works, this is likely not the problem.

I attached the schematic below, so you have a reference. Let me know if it helps.

Take care,

Joe

See pic below.
Oct 31, 2022 at 7:34 PM