No power to OBD2 port?

2018 GMC SIERRA
88,000 MILES • 6.2L • V8 • 4WD • AUTOMATIC
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MLUCAS47
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  • 2 POSTS
Failed inspection because there is no power to port so can't do MA emissions test. Contacts look good, auxiliary power ports have power (including cigarette lighters). Thinking it is a blown fuse, but I do not know which one.
Thanks
Mar 1, 2025 at 11:54 PM
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AL514
  • ✓Experienced Mechanic
  • 5,639 POSTS
Hello, the fuse for the DLC (pin 16) is the DLC/DSM Fuse 10amp in the left side dash fuse panel, I will post a wiring diagram as well. but check pins 4 and 5 for good Ground as well, when checking pin 16 for power, use pin 4, then pin 5 for ground to make sure it's good.
Mar 2, 2025 at 2:07 AM
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AL514
  • ✓Experienced Mechanic
  • 5,639 POSTS
Here's the fuse you're looking for and the pinout for the Data Link Connector.
Images (Click to enlarge)
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Professional Diagram for 2CarPros Members
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Mar 2, 2025 at 2:13 AM
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MLUCAS47
  • MEMBER
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DLC/DSM was position 25 and the fuse was indeed blown.
Thank you very much!
Mar 2, 2025 at 2:28 AM
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