No power to OBD2 port?

Tiny
MLUCAS47
  • MEMBER
  • 2018 GMC SIERRA
  • 6.2L
  • V8
  • 4WD
  • AUTOMATIC
  • 88,000 MILES
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
Sunday, March 2nd, 2025 AT 7:54 AM

3 Replies

Tiny
AL514
  • MECHANIC
  • 5,139 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.
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Sunday, March 2nd, 2025 AT 10:07 AM
Tiny
AL514
  • MECHANIC
  • 5,139 POSTS
Here's the fuse you're looking for and the pinout for the Data Link Connector.
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Sunday, March 2nd, 2025 AT 10:13 AM
Tiny
MLUCAS47
  • MEMBER
  • 2 POSTS
DLC/DSM was position 25 and the fuse was indeed blown.
Thank you very much!
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Sunday, March 2nd, 2025 AT 10:28 AM

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