No communication to DLC?

1997 CHEVROLET CAMARO
188,000 MILES • 5.7L • V8 • 2WD • MANUAL
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HAVER008
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  • 2 POSTS
I have no voltage going to the serial data wire on pin #2 on the DLC. I have checked all my fusses and I believe all the grounds. I checked the ECM to see if I could get a reading directly and still could not. Any assistance would be greatly appreciated.
Apr 17, 2024 at 12:09 AM
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STRAILER
  • CERTIFIED EXPERT
  • 53,870 POSTS
You should only have 12 volts at the orange wire in the ALDL connector which is powered by the CIGAR/ACCY fuse in the fuse panel inside the car. Here are the connector wiring diagrams so you can see how the system works and I have included the fuse location as well.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Check out the images (below). Let us know how it goes.


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Apr 17, 2024 at 10:37 AM
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HAVER008
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I have 12 volts to the orange wire. I also have approximately 5 volts to the other 2 data wires. But nothing on pin 2 the serial data wire. So I'm getting no communication reading on my scanner.
Apr 17, 2024 at 3:15 PM
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STRAILER
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Does the scanner work on other cars? Also did you check the ground wires to the connector? Blk and blk/wht. Please let me know. If the scanner works and you have grounds, please check the fuses for the PCM. If they are good then the PCM is bad, you can get a preprogrammed unit by searching Google or Ebay. Here is the location and how to replace it. Check out the images (below). Please let us know what happens.
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Apr 18, 2024 at 10:02 AM